kw: religion, atheism, popular culture
It is all over the news today, locally at least, that the city authorities in West Chester, Pennsylvania are under pressure by atheists, nontheists and humanists to restore the display of a "Tree of Knowledge" along with other "holiday greetings" on city property. It seems the City had been allowing all faiths and non-faiths to put up displays on city property, but in 2010 banned them all in favor of a few banners with neutral slogans, such as "Happy Holidays", that had been deemed non-confrontational by the Supreme Court. Now the anti-religion folks plan a rally/protest in hopes of convincing the city otherwise.
Of course, they don't want "Merry Christmas" banners or nativity scenes restored, just their tree of knowledge display. This demonstrates they are not just pro-nontheism, but anti-theism. That is, evangelical atheists are actually anti-theist. They don't disbelieve in God, they hate God or any idea of any god.
There are two partially conflicting principles that underlie democratic institutions, at least in the US. One is to do the greatest good for the greatest number. The other is to protect the rights of minorities. On the first principle, the greatest number of Americans are either Christian or sympathetic to Christian principles, and the next largest group is Jewish or sympathetic to them. On the other principle, the First Amendment to the Constitution guarantees us the right to practice our various religions according to our conscience. It does not guarantee the right of anybody to oppose another's religion, or the lack thereof.
The First Amendment actually contains the "Establishment Clause", which prohibits the Federal Government from establishing a religion to be the nationally practiced standard excluding all others. Thus the intimate relationship between the English government and the Anglican Church, or the German government and the Lutheran Church, are disallowed for the U.S. government. On this basis, I agree that specifically religious displays on government owned properties should not be allowed. If a business permits a religious display on its premises, that is OK, and the government has no right to an opinion about such things.
Is the "Tree of Knowledge" a specifically religious display? I say that it is. In particular, it is an anti-reaction to the story in Genesis in which God requires Adam and his wife to refrain from eating the "tree of the knowledge of good and evil". Note that the tree's designation is not pertaining to all knowledge, but to knowledge of moral issues. God wanted them to ask Him about moral issues instead; this is the basic Christian interpretation of this passage, and I think most Jews agree.
Let the City of West Chester regulate its own public spaces without regard to religion. If the atheists and their friends can persuade a business to display their Tree, fine and dandy. I wonder what the upshot will be…
Tuesday, November 29, 2011
Saturday, November 26, 2011
The most primitive life is still with us
kw: book reviews, nonfiction, viruses
I have read a number of books on viruses and virology, including a few that I have reviewed in this blog. The latest covers no new ground, but is a very informative introduction to the modern view of viruses: A Planet of Viruses by Carl Zimmer.
Using a baker's dozen case accounts to cover the breadth of the subject, Zimmer introduces us to viruses large and small, from ancient foes to recent eruptions. Though it may have been with us the longest, smallpox was the first to be cured, partly because it is the most obvious. In contrast to HIV, which is very recent, smallpox makes a person sick immediately, with unmistakable symptoms, and runs its course, deadly or not, in a few weeks. This has led to it being the first virus to be eradicated in the wild.
Viruses are fearsome in part because there are no known "beneficial" varieties. Just as snakes are universally predatory, viruses thrive only by parasitism of cellular organisms. As it happens, though, just as there are billions of bacteria for every "higher" organism, there are huge numbers of virus varieties that parasitize only bacteria and are thus beneficial to us. Before the discovery of antibiotics, viruses called bacteriophages (for "eaters of bacteria") were cultivated and used to cure bacterial diseases. Their only drawback is that viruses are very specific, so it takes quite a cocktail of phages is needed to combat bacteria that exist in multiple strains.
It is now known that the sea is a "virus ocean", with many millions of virus particles per liter of sea water. It is likely that, without viruses, the seas would become a cesspool of bacterial goop! The air is filled with suspended viruses as well, though to a lower density. As numerous as they are, viruses are so small that it takes a few million to outweigh the average bacterium, so they are (probably) not the heaviest component of the biosphere.
A recent discovery shows they are not all that small. Mimiviruses are called that because they mimic small bacteria. They are visible in an optical microscope, being about a micron in size. The smallest viruses known are one-hundredth the size, and most are about one-fortieth to one-twentieth that size.
The most interesting viruses to me are the retroviruses, those that insert their genomes within the genome of their host. So many of these have become "endogenous", meaning incorporated permanently, that about 8% of any animal's genome, including ours, consists of viruses that can be reactivated (according to other accounts I have read, about another quarter of our genome consists of fragmentary virus genomes).
If we consider the ways that life may have originated, it is likely that viruses may have either preceded the earliest cells, or that they arose along with them. That means that living things have never existed in isolation, but have always partaken of a grand kind of cross-species interbreeding facilitated by viruses. They are sometimes called the third sex, although before binary sex arose, they'd have been called the opposite sex! (were there anybody there with sufficient brains to do the calling).
The book is an easy read, and an enjoyable one. For many, it will introduce many subjects that one can then pursue in other works, and the bibliography contains plenty of excellent resources for that.
I have read a number of books on viruses and virology, including a few that I have reviewed in this blog. The latest covers no new ground, but is a very informative introduction to the modern view of viruses: A Planet of Viruses by Carl Zimmer.
Using a baker's dozen case accounts to cover the breadth of the subject, Zimmer introduces us to viruses large and small, from ancient foes to recent eruptions. Though it may have been with us the longest, smallpox was the first to be cured, partly because it is the most obvious. In contrast to HIV, which is very recent, smallpox makes a person sick immediately, with unmistakable symptoms, and runs its course, deadly or not, in a few weeks. This has led to it being the first virus to be eradicated in the wild.
Viruses are fearsome in part because there are no known "beneficial" varieties. Just as snakes are universally predatory, viruses thrive only by parasitism of cellular organisms. As it happens, though, just as there are billions of bacteria for every "higher" organism, there are huge numbers of virus varieties that parasitize only bacteria and are thus beneficial to us. Before the discovery of antibiotics, viruses called bacteriophages (for "eaters of bacteria") were cultivated and used to cure bacterial diseases. Their only drawback is that viruses are very specific, so it takes quite a cocktail of phages is needed to combat bacteria that exist in multiple strains.
It is now known that the sea is a "virus ocean", with many millions of virus particles per liter of sea water. It is likely that, without viruses, the seas would become a cesspool of bacterial goop! The air is filled with suspended viruses as well, though to a lower density. As numerous as they are, viruses are so small that it takes a few million to outweigh the average bacterium, so they are (probably) not the heaviest component of the biosphere.
A recent discovery shows they are not all that small. Mimiviruses are called that because they mimic small bacteria. They are visible in an optical microscope, being about a micron in size. The smallest viruses known are one-hundredth the size, and most are about one-fortieth to one-twentieth that size.
The most interesting viruses to me are the retroviruses, those that insert their genomes within the genome of their host. So many of these have become "endogenous", meaning incorporated permanently, that about 8% of any animal's genome, including ours, consists of viruses that can be reactivated (according to other accounts I have read, about another quarter of our genome consists of fragmentary virus genomes).
If we consider the ways that life may have originated, it is likely that viruses may have either preceded the earliest cells, or that they arose along with them. That means that living things have never existed in isolation, but have always partaken of a grand kind of cross-species interbreeding facilitated by viruses. They are sometimes called the third sex, although before binary sex arose, they'd have been called the opposite sex! (were there anybody there with sufficient brains to do the calling).
The book is an easy read, and an enjoyable one. For many, it will introduce many subjects that one can then pursue in other works, and the bibliography contains plenty of excellent resources for that.
Thursday, November 24, 2011
Thankful for a family that gets along
kw: holidays, family
We spent all day yesterday driving to my brother's house, where we'll have the holiday with them and another couple of relatives. Starting from a side trip in New Jersey, we got on I-80. Crossing Pennsylvania takes 309 miles, or about 6 hours, stops included.
We had a restful night in a hotel near my brother's house. The cousins (all young adults now) are having a good time together. Now, this morning we're all helping get dinner ready. My sister-in-law loves having help in the kitchen, and has a good kitchen for communal cooking. We're having great fun, talking and doing things together.
I hope the greatest number of people are having times together that they'll be thankful for. We're thankful not only for our past, but for memories we are making right now.
We spent all day yesterday driving to my brother's house, where we'll have the holiday with them and another couple of relatives. Starting from a side trip in New Jersey, we got on I-80. Crossing Pennsylvania takes 309 miles, or about 6 hours, stops included.
We had a restful night in a hotel near my brother's house. The cousins (all young adults now) are having a good time together. Now, this morning we're all helping get dinner ready. My sister-in-law loves having help in the kitchen, and has a good kitchen for communal cooking. We're having great fun, talking and doing things together.
I hope the greatest number of people are having times together that they'll be thankful for. We're thankful not only for our past, but for memories we are making right now.
Tuesday, November 22, 2011
The latest tear-jerker
kw: popular culture, tv shows, game shows
Last evening my wife and I watched ABC's new game show You Deserve It, mainly out of curiosity. My friends know I need three hankies at a two-hanky movie, so I kept a box of tissues handy in anticipation: the trailers showed plenty of tearful moments, and I figured I'd follow suit. I did. (My wife, on the other hand, is puzzled why I cry when I am happy or touched.)
A young woman won more than $110,000 on behalf of a friend, a young widow who has fallen on hard times. She had her own family there to support her, though they were not allowed to help her with the clues. It works like this: at each level you start with an amount of potential winnings, such as $50,000. You have to buy clues, and the amounts are random. You hope for low cost clues. If you buy every clue, you wind up with nothing. This contestant did pretty well. If you were to buy no clues, you could win more than $450,000. She did well to win about a quarter of that.
Because of the surprise factor involved, I reckon that all the episodes for this season have been taped already. ABC is trolling for more contestants, and I expect they'll get enough ratings for this show to continue for a few more seasons. Its first episode was warm-hearted enough, as we enter the holiday season, to keep plenty of viewers tearfully happy through the end of the year at least.
Last evening my wife and I watched ABC's new game show You Deserve It, mainly out of curiosity. My friends know I need three hankies at a two-hanky movie, so I kept a box of tissues handy in anticipation: the trailers showed plenty of tearful moments, and I figured I'd follow suit. I did. (My wife, on the other hand, is puzzled why I cry when I am happy or touched.)
A young woman won more than $110,000 on behalf of a friend, a young widow who has fallen on hard times. She had her own family there to support her, though they were not allowed to help her with the clues. It works like this: at each level you start with an amount of potential winnings, such as $50,000. You have to buy clues, and the amounts are random. You hope for low cost clues. If you buy every clue, you wind up with nothing. This contestant did pretty well. If you were to buy no clues, you could win more than $450,000. She did well to win about a quarter of that.
Because of the surprise factor involved, I reckon that all the episodes for this season have been taped already. ABC is trolling for more contestants, and I expect they'll get enough ratings for this show to continue for a few more seasons. Its first episode was warm-hearted enough, as we enter the holiday season, to keep plenty of viewers tearfully happy through the end of the year at least.
Monday, November 21, 2011
A foundation of my psyche
kw: book reviews, story reviews, science fiction, future fiction, anthologies
Richard Matheson is one writer whose stories helped me find myself and build myself as a young person. I began reading science fiction in a big way in 1967, and before long, I would simply go to the library's Science Fiction shelves each week and take out the next five books. It was a small library; I read everything they had in two years. I am Legend was one of the first novels I read that really affected me. Two stories by Matheson have also stuck with me in the years since: "Steel" and "The Traveller". How pleasant it was to find a recent collection of Matheson's stories, including the two last named: Steel and Other Stories. I'll simply provide teaser blurbs here:
Richard Matheson is one writer whose stories helped me find myself and build myself as a young person. I began reading science fiction in a big way in 1967, and before long, I would simply go to the library's Science Fiction shelves each week and take out the next five books. It was a small library; I read everything they had in two years. I am Legend was one of the first novels I read that really affected me. Two stories by Matheson have also stuck with me in the years since: "Steel" and "The Traveller". How pleasant it was to find a recent collection of Matheson's stories, including the two last named: Steel and Other Stories. I'll simply provide teaser blurbs here:
- Steel – In the boxing ring, human flesh is obsolete. A robot fighter breaks down, and ex-fighter Kelly decides to find out just how obsolete he is.
- To Fit the Crime – A demented poet, who never refrained from speaking his (acid) mind, is dying. What will his Hell be like?
- The Wedding – A prospective groom is obsessed with getting everything just perfect for his wedding.
- The Conqueror – A city boy with extraordinarily fast reflexes decides to make his name in the Old West as a gunfighter.
- Dear Diary – Women of different eras pour out their woes to their diaries.
- Descent – A giant bomb is going to destroy the surface of the Earth. People prepare to live underground.
- The Doll That Does Everything – A poet and his artist wife try to cope with an excessively destructive one-year-old by purchasing a robot playmate for him.
- The Traveller – A pioneer time traveler is sent to observe at Golgotha. The premise of this story helped me later attain faith.
- When Day is Dun – The last man on Earth after a disaster, a poet tries to chronicle his last feelings. (Matheson likes demented poets)
- The Splendid Source – Did you ever wonder who makes up all the dirty jokes going around?
- Lemmings – When overpopulation causes lemmings to clear out their food resources, they undertake mass migrations, with tragic results. Could this happen to people?
- The Edge – After a hard day, he just wants to take a break, but meets a total stranger who knows him. It gets stranger…
- A Visit to Santa Claus – A man with much on his mind tries to "help" his little son visit Santa Claus in the Mall.
- Dr. Morton's Folly – The last patient of the day has rather long teeth, but one needs a filling.
- The Window of Time – A man finds himself among scenes of his childhood. Is there any way to correct old mistakes?
Saturday, November 19, 2011
Without the three laws
kw: book reviews, science fiction, robots, future fiction
In his robot stories, Isaac Asimov explored the boundaries of the three laws he propounded to make intelligent machines safe for humanity. Famously neurotic, he wrote of robots that were sane while his human characters were typically neurotic. When an Asimov robot went bad, it was because one of the three laws was compromised. In his last novels, a robot became godlike, the only kind of a god he could believe in.
How do you implement such laws in actual machinery? How can we produce a machine with sufficient intellect to unfailingly recognize a human so it can obey? If we can take our cue from writers of robot stories, when genuinely intelligent mechanisms are produced, nobody will even bother. So when a real robot scientist writes of robots that go awry, I take notice.
Robopocalypse by Daniel H. Wilson is misnamed; "Apocalypse" simply means revelation. To connect the story with the ultimate battle, the title ought to be "Robogeddon". With that quibble out of the way, I was captivated by the story. The book is such a page-turner that I finished it today, a day or two before I'd expected. Kudos to the author!
One premise of the story is that putting lots of "intelligence" into cars, phones, radios, toasters and coffee makers has become so cheap that an intelligent chip has been installed in almost everything. A second is that robot servants, based on this bright chip, have multiplied to the point that in a "civilized" home, they outnumber the people about two to one. Then a scientist, working in a well-shielded bunker, puts together a whole lot of such chips and somehow programs the combination to become self-aware. Once the infant mind named Archos has assimilated all the databases made available within this bunker, it decides humanity is obsolete, kills the scientist, and takes steps to eliminate the human race.
Why not simply evolve alongside? As Archos says later on, "It is not enough to live together in peace, with one race on its knees." (While this sounds Lincolnesque, it is a paraphrase of several things Lincoln wrote.) Archos, we find, is very interested in life, just not human life. So it hacks its way into everything and takes over all the robots and other intelligent systems that underpin civilization.
The book is the story of the war that follows. Of course, humanity wins. Humankind and robotkind learn to exploit one another's weaknesses. In this case, the humans learn faster. As the lead human character, Cormac Wallace, says, "Human beings adapt. It's what we do." Will it always be so? is the lingering question the book leaves behind.
On the last page of a recent issue of Scientific American it was shown in an amazing graphic that the most powerful supercomputer (at present) is now just a little faster in total processing power, and has a larger memory capacity, than a human brain. The brain weighs about 1.6 kg and uses 20-30 watts of sugar-based energy. You could say that the human body that holds the brain is its support system, including cooling: another 30-100 kg. The supercomputer weighs about a ton, its support systems and cooling plant weigh another few tons. Its power requirement is nine megawatts, and I presume the cooling plant requires at least three megawatts.
How long will it be until this level of compute power and memory capacity can be fit in a breadbox and uses 100 watts or less? Here is a way to make a rough estimate. In 1976 a Cray-1 supercomputer was the first machine to achieve 100 MFlops (100 million numerical calculations per second). It cost almost $9 million, stood six feet high, and used thousands of watts of power. Earlier this year my son and I constructed a desktop computer for me, which is capable of about 100 MFlops per processor; it has four processors. The main 4-processor chip uses 150 watts; the whole package uses less than 500 watts. It cost $700. 2011-1976 = 35 years. This implies that a "one brain" computer costing $1,000 in today's currency might be on off-the-shelf item in about 2040-2045. I won't be 100 yet.
How long after that before robots outnumber people? And will it then be possible for such brain-boxes to become self-aware? And what will they do about it? Robopocalypse provides one man's answer. Just to comfort you, Wilson has also written How to Survive a Robot Uprising.
In his robot stories, Isaac Asimov explored the boundaries of the three laws he propounded to make intelligent machines safe for humanity. Famously neurotic, he wrote of robots that were sane while his human characters were typically neurotic. When an Asimov robot went bad, it was because one of the three laws was compromised. In his last novels, a robot became godlike, the only kind of a god he could believe in.
How do you implement such laws in actual machinery? How can we produce a machine with sufficient intellect to unfailingly recognize a human so it can obey? If we can take our cue from writers of robot stories, when genuinely intelligent mechanisms are produced, nobody will even bother. So when a real robot scientist writes of robots that go awry, I take notice.
Robopocalypse by Daniel H. Wilson is misnamed; "Apocalypse" simply means revelation. To connect the story with the ultimate battle, the title ought to be "Robogeddon". With that quibble out of the way, I was captivated by the story. The book is such a page-turner that I finished it today, a day or two before I'd expected. Kudos to the author!
One premise of the story is that putting lots of "intelligence" into cars, phones, radios, toasters and coffee makers has become so cheap that an intelligent chip has been installed in almost everything. A second is that robot servants, based on this bright chip, have multiplied to the point that in a "civilized" home, they outnumber the people about two to one. Then a scientist, working in a well-shielded bunker, puts together a whole lot of such chips and somehow programs the combination to become self-aware. Once the infant mind named Archos has assimilated all the databases made available within this bunker, it decides humanity is obsolete, kills the scientist, and takes steps to eliminate the human race.
Why not simply evolve alongside? As Archos says later on, "It is not enough to live together in peace, with one race on its knees." (While this sounds Lincolnesque, it is a paraphrase of several things Lincoln wrote.) Archos, we find, is very interested in life, just not human life. So it hacks its way into everything and takes over all the robots and other intelligent systems that underpin civilization.
The book is the story of the war that follows. Of course, humanity wins. Humankind and robotkind learn to exploit one another's weaknesses. In this case, the humans learn faster. As the lead human character, Cormac Wallace, says, "Human beings adapt. It's what we do." Will it always be so? is the lingering question the book leaves behind.
On the last page of a recent issue of Scientific American it was shown in an amazing graphic that the most powerful supercomputer (at present) is now just a little faster in total processing power, and has a larger memory capacity, than a human brain. The brain weighs about 1.6 kg and uses 20-30 watts of sugar-based energy. You could say that the human body that holds the brain is its support system, including cooling: another 30-100 kg. The supercomputer weighs about a ton, its support systems and cooling plant weigh another few tons. Its power requirement is nine megawatts, and I presume the cooling plant requires at least three megawatts.
How long will it be until this level of compute power and memory capacity can be fit in a breadbox and uses 100 watts or less? Here is a way to make a rough estimate. In 1976 a Cray-1 supercomputer was the first machine to achieve 100 MFlops (100 million numerical calculations per second). It cost almost $9 million, stood six feet high, and used thousands of watts of power. Earlier this year my son and I constructed a desktop computer for me, which is capable of about 100 MFlops per processor; it has four processors. The main 4-processor chip uses 150 watts; the whole package uses less than 500 watts. It cost $700. 2011-1976 = 35 years. This implies that a "one brain" computer costing $1,000 in today's currency might be on off-the-shelf item in about 2040-2045. I won't be 100 yet.
How long after that before robots outnumber people? And will it then be possible for such brain-boxes to become self-aware? And what will they do about it? Robopocalypse provides one man's answer. Just to comfort you, Wilson has also written How to Survive a Robot Uprising.
Friday, November 18, 2011
Sure he is great, just ask him
kw: book reviews, nonfiction, memoirs, celebrities
During my last two years in my parents' home, there was a ritual a couple nights a week: Mom would prepare dinner, then take her plate to the next room to watch Star Trek. I, and at least one or two of my brothers, would join her there. For a show that was generally considered "not well received", it obtained quite a cult following that continues today. The cultus was vindicated when the cast was reassembled over a decade or so to produce seven feature films.
I have also read a lot about how the cast members didn't get along, particularly with the star. Several of them considered William Shatner to be insufferably arrogant, and some would never be seen with him off the set. In Shatner Rules: Your Guide to Understanding the Shatnerverse and the World at Large, written with Chris Regan, Bill Shatner lays out all of his career. By 1970, he considered Star Trek as little more than a blip in the road, until the uproar arose that led to those films. And he has his own take on the arrogance thing. Yes, he was arrogant, and he still is, with good reason: he's good (just ask him).
The young Captain Kirk is how I and many of my friends remember William Shatner. The more mature actor who starred in Boston Legal and several other TV series is less familiar to us (at least to me; I seldom watch TV series). Now, at age 80 (the second pic was taken on his birthday), Bill is still going nonstop.
The book is constructed around a number of his Rules, the first being, "Say 'Yes!'". As long as we are about rules, here is one my father passed on to me:
Bill Shatner is someone who knows his strengths. He is an actor. He has been an actor since he was six. As of March 22 this year, that makes 74 years in which the only thing he has been paid to do is to act. Or so he says. He has produced and participated (perhaps starred, at least in his estimation) in several albums of music. So he's been paid to do just a bit of singing. He directed one of the Star Trek films; did he accept a director's salary, or was he sufficiently compensated as the star of the film? Yet, first and foremost, he is an actor.
Finally, I have to say, one thing I really liked about Star Trek was that the Captain, and others, were literate. Literary quotes were used in a number of episodes. I sometimes wondered if that was all the writers' doing, or if William Shatner was literate himself? At least to some extent, yes he is, not that he has a great deal of time to read! In one chapter he takes us through an ordinary "Two Shatner Day", meaning a day in which he has about twice as much stuff scheduled as the clock allows. Somehow, he accomplished it all. He does admit that a "Four Shatner Day" makes his head explode.
As long as you are going to turn 80 anyway, it's better to keep active. And while you are at it, remember who you love.
During my last two years in my parents' home, there was a ritual a couple nights a week: Mom would prepare dinner, then take her plate to the next room to watch Star Trek. I, and at least one or two of my brothers, would join her there. For a show that was generally considered "not well received", it obtained quite a cult following that continues today. The cultus was vindicated when the cast was reassembled over a decade or so to produce seven feature films.
I have also read a lot about how the cast members didn't get along, particularly with the star. Several of them considered William Shatner to be insufferably arrogant, and some would never be seen with him off the set. In Shatner Rules: Your Guide to Understanding the Shatnerverse and the World at Large, written with Chris Regan, Bill Shatner lays out all of his career. By 1970, he considered Star Trek as little more than a blip in the road, until the uproar arose that led to those films. And he has his own take on the arrogance thing. Yes, he was arrogant, and he still is, with good reason: he's good (just ask him).
The young Captain Kirk is how I and many of my friends remember William Shatner. The more mature actor who starred in Boston Legal and several other TV series is less familiar to us (at least to me; I seldom watch TV series). Now, at age 80 (the second pic was taken on his birthday), Bill is still going nonstop.
The book is constructed around a number of his Rules, the first being, "Say 'Yes!'". As long as we are about rules, here is one my father passed on to me:
Jim's First Rule – Don't say bad things about yourself. The world is full of people who will do that for you.And as for arrogance, I don't mind it so much. I first learned about "creative arrogance" from my Dad, of course, and I also love the jokingly arrogant attitude Rush Limbaugh adopts, to the point that I sometimes open an inspirational speech by saying, "Rush says he has talent on loan from God. I've never felt I needed to borrow any." (Spoiler alert: In case you hear one of my speeches, you need to realize the message is simple. If two people agree on everything, one of them is redundant. Don't be afraid to differ. Just don't differ to the point that children run for the exits or hunker under chairs.)
Bill Shatner is someone who knows his strengths. He is an actor. He has been an actor since he was six. As of March 22 this year, that makes 74 years in which the only thing he has been paid to do is to act. Or so he says. He has produced and participated (perhaps starred, at least in his estimation) in several albums of music. So he's been paid to do just a bit of singing. He directed one of the Star Trek films; did he accept a director's salary, or was he sufficiently compensated as the star of the film? Yet, first and foremost, he is an actor.
Finally, I have to say, one thing I really liked about Star Trek was that the Captain, and others, were literate. Literary quotes were used in a number of episodes. I sometimes wondered if that was all the writers' doing, or if William Shatner was literate himself? At least to some extent, yes he is, not that he has a great deal of time to read! In one chapter he takes us through an ordinary "Two Shatner Day", meaning a day in which he has about twice as much stuff scheduled as the clock allows. Somehow, he accomplished it all. He does admit that a "Four Shatner Day" makes his head explode.
As long as you are going to turn 80 anyway, it's better to keep active. And while you are at it, remember who you love.
Thursday, November 17, 2011
Energy Spectrum
kw: analysis, observations, particle physics
While a number of web sites illustrate the energy spectrum, none covers the entire useful range. This picture shows a chart that I'd have preferred as a table, but this blogging tool does a particularly bad job displaying tables. To see the table more clearly, right click on it and choose "Open Link in New Tab" or "Open Link in New Window".
While this might be called the electromagnetic spectrum, I have specifically included a range of energies very seldom probed by photons, energies higher than a few GeV, which are typically found only in baryons accelerated by synchrotrons and in cosmic rays. At these high energies, the particles are moving close enough to c that the wavelength-energy conversion is a reasonable approximation.
This is an energy spectrum, so the table is based on the energy, in electron-volts (eV) in the first two columns. Column 1 is the lower limit of a decade range shown in scientific notation, and Column 2 (blue) shows more conventional units for each range, from 100 femto-eV (feV) to 1 Zetta-eV (ZeV). The reason I went no further will be explained later on.
The central column, wavelength (λ), ranges downward from tens of thousands of km to the yoctometer (ym) range, and smaller. The ym is the smallest defined length unit, though I suppose I could have expressed these shorter wavelengths in Planck units. The conversion from E to λ is hc, or 1.2398419 eV-μ, which is 1.2398419x10-6 eV-m. Rounding to 1.24 eV-μ introduces only a small error, about 0.01%.
The next column, frequency (f, brown), is proportional to energy, and ranges from a few Hz to many YottaHertz (YHz) and higher. This is the highest frequency we have a defined prefix for. The conversion from λ to f is the speed of light, 299,792,458 m/s. Rounding to 3x108 introduces an error less than 0.1%.
Finally, each range has a descriptive term applied, but we should realize there is quite a bit of overlap between some of the ranges. For example, extreme UV and soft x-rays overlap, and the term used depends on how someone is using them. Now let's take a little tour.
We seldom realize it, but we are constantly bathed in a low level of either 50- or 60-Hz "hum" from fluorescent lights, electric motors and other things energized by "wall current". The last time I was in Japan, I noticed that the power in the Tokyo area was 60 Hz, but the rest of the country was still using 50 Hz power. It made a difference in how my electric shaver sounded. By working backward through the conversions, we find that 50 and 60 Hz have wavelengths of 6,000 and 5,000 km, respectively, and photon energies of 2.067x10-13 and 2.48x10-13 eV. In ranges much below 1 eV, photon energy doesn't mean much, because the photoelectric effect or other particle interactions don't operate.
The highest note on a piano is 4,186 Hz (4.186 kHz), based on standard tuning of A=440 Hz. The electromagnetic wavelength of this note is 71.7 km, but the acoustic wavelength in standard, sea-level air is 81mm.
The high squeal of an old, CRT-type TV set is 14.75 kHz, which young people can hear, but oldsters like me cannot. Its EM wavelength is 20.3 km.
I am a radio ham. The lowest frequency hams can use at present is 1.8 MHz, which has a wavelength of 167 m. The band's upper edge is 2 Mhz, with a wavelength of 150 m. The band is called the 160 meter band. There are a large number of amateur and international broadcast short-wave bands in the HF (high frequency) range. The most popular are near 14 MHz, the ham's "20-meter band" (14.0-14.35 MHz, with wavelengths of 21.4-20.0 m) and the broadcasters' "19-meter band" (15.1-15.9 MHz, and 19.9-19.0 m wavelength).
VHF and UHF designate frequencies from 30-300 and 300-3,000 MHz. This very useful range is filled with broadcast TV, point-to-point radio, cellular phone services, and at 2,450 MHz (2.45 GHz), microwave ovens. The microwave oven wavelength is 122 mm. This is a compromise frequency. Firstly, it was a political compromise, as various regulatory bodies had to determine a frequency range that wouldn't interfere with existing communications and control services. But using this frequency rather than one much higher or lower is also a compromise. Microwave ovens don't heat evenly because the way the waves bounce around inside the cavity creates higher- and lower-power spots. A much lower frequency would heat more evenly, but much less efficiently. A very much higher frequency would also heat more evenly, but the heat would not penetrate very deeply into the food, and penetration was considered more important than evenness of heating. Besides, most modern microwave ovens have turntables; just be sure to put the item being heated a little off center, which helps the waves spread around better.
The range of energies considered "radio+microwave" keeps expanding. The current limit is about 100 GHz, with wavelengths near 0.3 mm. Above this is the T-ray or T-wave realm, from 0.1 to 100 THz. These are just beginning to be used in place of backscattered x-rays for screening airport passengers for weapons. They can allow an operator to see weapons that a metal detector would miss. The trouble is, with their sub-millimeter resolution and ability to pass right through most fabrics, they produce a "naked" image of a person, so at least in America, there are huge privacy fights going on about them. Personally, I figure if an operator, whether male or female, gets a few jollies from seeing a T-wave image of me, that's not my problem, it is his or hers.
Wavelengths shorter than about 0.1mm are called extreme infrared (EIR), and the IR ranges through far IR (FIR, but used rarely) to near IR, which ends at 0.7μ, at the red end of visible light. The remote control that runs your TV uses one of two IR wavelengths, either 0.8μ or 1.2μ, both of which are pretty easy to produce and detect. The shorter wavelength is less common, because many Asian people can see it. The frequency of 0.8μ is 375 THz, and of 1.2μ is 250 THz. Here the photoelectric effect gets going well enough that it is worth reporting the energies: 1.55 and 1.03 eV, respectively.
The wavelength of greatest visibility is usually quoted as 555nm (0.555μ), with a frequency of 540 THz and a photon energy of 2.23 eV. The bluest light usually seen is at 400 nm, although people who have had cataracts removed can see near-UV light as "blue" as 360 nm. These limits have frequencies of 750 and 833 THz, respectively, and photon energies of 3.10 and 3.44 eV.
Light bluer than about 300 nm is absorbed by the atmosphere, but shorter wavelengths in the "vacuum UV" range are very useful for chemical identification. They are also useful for astronomy, so far-UV and extreme-UV telescopes have been placed in orbit. The conventional limit of UV astronomy is 91.2 nm, because shorter wavelengths are strongly absorbed by neutral hydrogen in space. This limit's frequency is 3,290 THz or 3.29 PHz. Above the PetaHertz range we seldom mention frequency, because we are in the realm of particle behavior. This limit has a photon energy of 13.6 eV, which is enough to totally ionize a hydrogen atom.
X-rays are defined as electromagnetic radiation produced by accelerated electrons, further delimited as ionizing, so the softest x-rays are the 92.1 nm radiation that ionizes hydrogen.
From this point, particle energy is the key parameter and secondarily, wavelength. The beginning of the soft x-ray range is conventionally 10 nm, with photon energy of 124 eV. X-rays are not very penetrating at energies below about 1 keV, which has a wavelength of 1.24 nm. Your doctor's or dentist's x-ray machine uses a broad-spectrum source with a peak near 60 keV and a wavelength near 0.02 nm or 20 pm. In older literature, this was called 0.2 Angstroms. The hardest x-rays are about twice this energetic, at 120 keV and 10 pm wavelength.
Gamma radiation originates in the atomic nucleus, or by energetic particle interactions such as electron-positron annihilation. The softest gamma rays are about as energetic as soft x-rays, but the typical gamma ray has an energy of one or more MeV. Gamma rays as energetic as 6 MeV are produced by alpha emitters such as Uranium; such a photon has a wavelength of 0.2 pm or 200 fm (femtometers). Gamma ray photons and other particles with such energies are useful probes of the nucleus, which is also measured in fm.
One useful gamma radiation energy is 511 keV, which equals the rest mass of an electron. When an electron and a positron annihilate each other, they produce two gamma rays with this energy (and a 2 pm wavelength). In particle accelerators, protons and antiprotons are produced in copious amounts. Annihilation radiation for proton-antiproton interaction is a pair of gamma ray photons with an energy of 938 MeV. This near-GeV range is the upper limit of useful gamma ray photon energies. There are no natural processes that produce photons above this range, except scattering of lower-energy photons by cosmic rays.
Cosmic rays are not photons, they are matter particles: mostly protons, a few electrons, and even fewer heavier nuclei. They come in energies throughout the energy range, but particles with less than 9 GeV don't make it through the Earth's magnetic field. Some are guided by the field to Earth's poles, where they stimulate aurorae. More energetic particles reach the atmosphere and scatter off atmospheric atoms to create air showers of less energetic particles. Detecting and summing up an air shower allows us to characterize the original particle, at least by its incoming energy.
The spectrum of cosmic rays is scale-free, smoothly descending in numbers with higher energies, to a cutoff near 6x1019 eV. Above this energy, an energetic proton that has traveled more than a hundred million parsecs will have scattered off many photons of the cosmic background radiation, losing energy even while it produces those rare multi-GeV photons. In spite of this, a few huge air showers have been detected that indicate an ultra-high-energy cosmic ray occasionally makes it through to Earth with an energy between 1 and 3x1020 eV. That last represents a proton with the energy of a well thrown baseball, as much as 50 Joules.
It is not known how the most energetic cosmic rays originate. Perhaps a proton-proton collision can give one a "kick" at the expense of the other, near enough to Earth that CMB scattering doesn't bleed off too much energy. I suspect the limit of my scale, at 1021 eV, will never be detected. The air shower would be larger than the largest detector array we can build on the planet's surface!
Tour over. You may now unbuckle your seat belt and disembark.
While a number of web sites illustrate the energy spectrum, none covers the entire useful range. This picture shows a chart that I'd have preferred as a table, but this blogging tool does a particularly bad job displaying tables. To see the table more clearly, right click on it and choose "Open Link in New Tab" or "Open Link in New Window".
While this might be called the electromagnetic spectrum, I have specifically included a range of energies very seldom probed by photons, energies higher than a few GeV, which are typically found only in baryons accelerated by synchrotrons and in cosmic rays. At these high energies, the particles are moving close enough to c that the wavelength-energy conversion is a reasonable approximation.
This is an energy spectrum, so the table is based on the energy, in electron-volts (eV) in the first two columns. Column 1 is the lower limit of a decade range shown in scientific notation, and Column 2 (blue) shows more conventional units for each range, from 100 femto-eV (feV) to 1 Zetta-eV (ZeV). The reason I went no further will be explained later on.
The central column, wavelength (λ), ranges downward from tens of thousands of km to the yoctometer (ym) range, and smaller. The ym is the smallest defined length unit, though I suppose I could have expressed these shorter wavelengths in Planck units. The conversion from E to λ is hc, or 1.2398419 eV-μ, which is 1.2398419x10-6 eV-m. Rounding to 1.24 eV-μ introduces only a small error, about 0.01%.
The next column, frequency (f, brown), is proportional to energy, and ranges from a few Hz to many YottaHertz (YHz) and higher. This is the highest frequency we have a defined prefix for. The conversion from λ to f is the speed of light, 299,792,458 m/s. Rounding to 3x108 introduces an error less than 0.1%.
Finally, each range has a descriptive term applied, but we should realize there is quite a bit of overlap between some of the ranges. For example, extreme UV and soft x-rays overlap, and the term used depends on how someone is using them. Now let's take a little tour.
Acoustic Range
We seldom realize it, but we are constantly bathed in a low level of either 50- or 60-Hz "hum" from fluorescent lights, electric motors and other things energized by "wall current". The last time I was in Japan, I noticed that the power in the Tokyo area was 60 Hz, but the rest of the country was still using 50 Hz power. It made a difference in how my electric shaver sounded. By working backward through the conversions, we find that 50 and 60 Hz have wavelengths of 6,000 and 5,000 km, respectively, and photon energies of 2.067x10-13 and 2.48x10-13 eV. In ranges much below 1 eV, photon energy doesn't mean much, because the photoelectric effect or other particle interactions don't operate.
The highest note on a piano is 4,186 Hz (4.186 kHz), based on standard tuning of A=440 Hz. The electromagnetic wavelength of this note is 71.7 km, but the acoustic wavelength in standard, sea-level air is 81mm.
The high squeal of an old, CRT-type TV set is 14.75 kHz, which young people can hear, but oldsters like me cannot. Its EM wavelength is 20.3 km.
Radio
I am a radio ham. The lowest frequency hams can use at present is 1.8 MHz, which has a wavelength of 167 m. The band's upper edge is 2 Mhz, with a wavelength of 150 m. The band is called the 160 meter band. There are a large number of amateur and international broadcast short-wave bands in the HF (high frequency) range. The most popular are near 14 MHz, the ham's "20-meter band" (14.0-14.35 MHz, with wavelengths of 21.4-20.0 m) and the broadcasters' "19-meter band" (15.1-15.9 MHz, and 19.9-19.0 m wavelength).
VHF and UHF designate frequencies from 30-300 and 300-3,000 MHz. This very useful range is filled with broadcast TV, point-to-point radio, cellular phone services, and at 2,450 MHz (2.45 GHz), microwave ovens. The microwave oven wavelength is 122 mm. This is a compromise frequency. Firstly, it was a political compromise, as various regulatory bodies had to determine a frequency range that wouldn't interfere with existing communications and control services. But using this frequency rather than one much higher or lower is also a compromise. Microwave ovens don't heat evenly because the way the waves bounce around inside the cavity creates higher- and lower-power spots. A much lower frequency would heat more evenly, but much less efficiently. A very much higher frequency would also heat more evenly, but the heat would not penetrate very deeply into the food, and penetration was considered more important than evenness of heating. Besides, most modern microwave ovens have turntables; just be sure to put the item being heated a little off center, which helps the waves spread around better.
The range of energies considered "radio+microwave" keeps expanding. The current limit is about 100 GHz, with wavelengths near 0.3 mm. Above this is the T-ray or T-wave realm, from 0.1 to 100 THz. These are just beginning to be used in place of backscattered x-rays for screening airport passengers for weapons. They can allow an operator to see weapons that a metal detector would miss. The trouble is, with their sub-millimeter resolution and ability to pass right through most fabrics, they produce a "naked" image of a person, so at least in America, there are huge privacy fights going on about them. Personally, I figure if an operator, whether male or female, gets a few jollies from seeing a T-wave image of me, that's not my problem, it is his or hers.
Near-Visible and Visible Ranges
Wavelengths shorter than about 0.1mm are called extreme infrared (EIR), and the IR ranges through far IR (FIR, but used rarely) to near IR, which ends at 0.7μ, at the red end of visible light. The remote control that runs your TV uses one of two IR wavelengths, either 0.8μ or 1.2μ, both of which are pretty easy to produce and detect. The shorter wavelength is less common, because many Asian people can see it. The frequency of 0.8μ is 375 THz, and of 1.2μ is 250 THz. Here the photoelectric effect gets going well enough that it is worth reporting the energies: 1.55 and 1.03 eV, respectively.
The wavelength of greatest visibility is usually quoted as 555nm (0.555μ), with a frequency of 540 THz and a photon energy of 2.23 eV. The bluest light usually seen is at 400 nm, although people who have had cataracts removed can see near-UV light as "blue" as 360 nm. These limits have frequencies of 750 and 833 THz, respectively, and photon energies of 3.10 and 3.44 eV.
Light bluer than about 300 nm is absorbed by the atmosphere, but shorter wavelengths in the "vacuum UV" range are very useful for chemical identification. They are also useful for astronomy, so far-UV and extreme-UV telescopes have been placed in orbit. The conventional limit of UV astronomy is 91.2 nm, because shorter wavelengths are strongly absorbed by neutral hydrogen in space. This limit's frequency is 3,290 THz or 3.29 PHz. Above the PetaHertz range we seldom mention frequency, because we are in the realm of particle behavior. This limit has a photon energy of 13.6 eV, which is enough to totally ionize a hydrogen atom.
X-Rays
X-rays are defined as electromagnetic radiation produced by accelerated electrons, further delimited as ionizing, so the softest x-rays are the 92.1 nm radiation that ionizes hydrogen.
From this point, particle energy is the key parameter and secondarily, wavelength. The beginning of the soft x-ray range is conventionally 10 nm, with photon energy of 124 eV. X-rays are not very penetrating at energies below about 1 keV, which has a wavelength of 1.24 nm. Your doctor's or dentist's x-ray machine uses a broad-spectrum source with a peak near 60 keV and a wavelength near 0.02 nm or 20 pm. In older literature, this was called 0.2 Angstroms. The hardest x-rays are about twice this energetic, at 120 keV and 10 pm wavelength.
Gamma Radiation
Gamma radiation originates in the atomic nucleus, or by energetic particle interactions such as electron-positron annihilation. The softest gamma rays are about as energetic as soft x-rays, but the typical gamma ray has an energy of one or more MeV. Gamma rays as energetic as 6 MeV are produced by alpha emitters such as Uranium; such a photon has a wavelength of 0.2 pm or 200 fm (femtometers). Gamma ray photons and other particles with such energies are useful probes of the nucleus, which is also measured in fm.
One useful gamma radiation energy is 511 keV, which equals the rest mass of an electron. When an electron and a positron annihilate each other, they produce two gamma rays with this energy (and a 2 pm wavelength). In particle accelerators, protons and antiprotons are produced in copious amounts. Annihilation radiation for proton-antiproton interaction is a pair of gamma ray photons with an energy of 938 MeV. This near-GeV range is the upper limit of useful gamma ray photon energies. There are no natural processes that produce photons above this range, except scattering of lower-energy photons by cosmic rays.
Cosmic Rays
Cosmic rays are not photons, they are matter particles: mostly protons, a few electrons, and even fewer heavier nuclei. They come in energies throughout the energy range, but particles with less than 9 GeV don't make it through the Earth's magnetic field. Some are guided by the field to Earth's poles, where they stimulate aurorae. More energetic particles reach the atmosphere and scatter off atmospheric atoms to create air showers of less energetic particles. Detecting and summing up an air shower allows us to characterize the original particle, at least by its incoming energy.
The spectrum of cosmic rays is scale-free, smoothly descending in numbers with higher energies, to a cutoff near 6x1019 eV. Above this energy, an energetic proton that has traveled more than a hundred million parsecs will have scattered off many photons of the cosmic background radiation, losing energy even while it produces those rare multi-GeV photons. In spite of this, a few huge air showers have been detected that indicate an ultra-high-energy cosmic ray occasionally makes it through to Earth with an energy between 1 and 3x1020 eV. That last represents a proton with the energy of a well thrown baseball, as much as 50 Joules.
It is not known how the most energetic cosmic rays originate. Perhaps a proton-proton collision can give one a "kick" at the expense of the other, near enough to Earth that CMB scattering doesn't bleed off too much energy. I suspect the limit of my scale, at 1021 eV, will never be detected. The air shower would be larger than the largest detector array we can build on the planet's surface!
Tour over. You may now unbuckle your seat belt and disembark.
Wednesday, November 16, 2011
The builders all around us
kw: book reviews, nonfiction, natural history, birds, nests, photographs
I think we have all seen many pictures like this one, of a bird feeding chicks. This goldfinch is bringing a seed to his offspring in the "standard" cup-shaped nest. As I read in Avian Architecture: How Birds Design, Engineer and Build by Peter Goodfellow, about half of all bird species make this kind of nest, from tiny hummingbirds to robins to crows. This image is from page 57 of the book; click on it for a larger version, but see the book for a full-page beauty of an image.
Such nests are about halfway along a scale of ambition, which the book seems to follow. The simplest nests are scrapes, such as the rocky rings pulled together by terns and some gulls. Some birds build small or modified cup nests inside ready-made holes, while others such as woodpeckers and burrowing owls make their own holes. Platform nests may start as a scrape, if built on the ground, but a large structure is piled up, often to raise the eggs above rainfall runoff or just the chilly soil. But the most familiar platforms are those built by raptors such as eagles, high in trees or on a cliffy ledge.
There is a spectrum from platform nests built on the ground to floating nests, with aquatic platforms somewhere in the middle: a bird will pile up a platform of rocks and mud in shallow water until it reaches the surface, then top it with plant materials for another few (or many) inches, so that it holds the eggs above the water, but is moated from predators. Other aquatic nests are woven to reeds or stalks and constructed of light materials so that they can float and support the eggs and a sitting parent. Properly attached, they can rise and fall with the water.
Birds a little more ambitious than cup-makers build a dome over a cup. At this point, five chapters have been spent on nests largely produced from plant materials, at least the top part. Chapter six is on mud nests, and this image of a cliff swallow colony is one of the most stunning in the book (page 93). Barn swallows build nests that are similar, if more open, but to my observation, are nearly always solitary. It takes hundreds of flights, carrying a small ball of mud in the beak, to build a mud nest. During the carrying, some saliva gets mixed in, which increases the adhesive properties of the mud.
We return to plant materials when we consider hanging nests, which are usually stitched or woven, such as the oriole nest. Orioles and other weaving birds work harder than most others, and it takes a long time, working with only a beak, to weave their elaborate nests. I remember getting a fallen oriole nest, and trying to figure out how the strands were put together. With my ten fingers and the help of tweezers, I was scarcely able to untwine just a strand or two.
Not all woven nests are pendulous, of course. Some look superficially like a cup nest, but are woven of stranded materials such as grass blades and hang together better than the twiggy nests with which we are most familiar. Key to their success is that they give under pressure, so the initial nest just barely fits the clutch of eggs and the sitting parent, but stretches as the chicks grow.
Mound nests may sometimes be rather simple, as the nests of these flamingos (page 109), but some are very large. Some mound-builders fill the middle of the mound with leaves and leaf litter, and bury the eggs within, so that the composting stuff keeps the eggs warm. These birds don't sit on the eggs, and typically abandon them once they are certain the composting temperature is right. Flamingos and others do incubate the eggs by sitting. Many penguin species also make mound nests.
The tenth chapter is on group nests. These cover the gamut of building styles and materials. Their common element is that multiple bird pairs nest, each in its own "apartment", in a large structure built by all the pairs.
Not all structures built by birds are for nesting and caring for young. Bowers and courts are major examples of nestlike structures that a male bird produces to impress females and induce them to mate with him. Males of bowerbirds and their relatives do not care for the young. After mating, a female goes off alone and builds a small cup nest in a hidden location.
The last chapter is half about "edible" nests, the ones used in bird-nest soup, and half about caches of food that certain woodpeckers produce, often by making a "mailbox" of holes in a dead tree trunk and filling the holes with acorns. As to the soup-nests; I can't imagine eating bird spit, which is the only construction material for the "white" swiftlet nest. Yet there is big business in cultivating swiftlets in Indonesia, where special buildings are constructed for the birds to nest in. Chacun à son gout!
The book is lavishly illustrated, and each chapter contains a "blueprint" page, with specifications for typical nests of each type, plus three or more case studies of a few species. While it is enjoyable to read right through, it is also a valuable reference book, and a good companion book to the field guides we use, which have little information on nests.
I think we have all seen many pictures like this one, of a bird feeding chicks. This goldfinch is bringing a seed to his offspring in the "standard" cup-shaped nest. As I read in Avian Architecture: How Birds Design, Engineer and Build by Peter Goodfellow, about half of all bird species make this kind of nest, from tiny hummingbirds to robins to crows. This image is from page 57 of the book; click on it for a larger version, but see the book for a full-page beauty of an image.
Such nests are about halfway along a scale of ambition, which the book seems to follow. The simplest nests are scrapes, such as the rocky rings pulled together by terns and some gulls. Some birds build small or modified cup nests inside ready-made holes, while others such as woodpeckers and burrowing owls make their own holes. Platform nests may start as a scrape, if built on the ground, but a large structure is piled up, often to raise the eggs above rainfall runoff or just the chilly soil. But the most familiar platforms are those built by raptors such as eagles, high in trees or on a cliffy ledge.
There is a spectrum from platform nests built on the ground to floating nests, with aquatic platforms somewhere in the middle: a bird will pile up a platform of rocks and mud in shallow water until it reaches the surface, then top it with plant materials for another few (or many) inches, so that it holds the eggs above the water, but is moated from predators. Other aquatic nests are woven to reeds or stalks and constructed of light materials so that they can float and support the eggs and a sitting parent. Properly attached, they can rise and fall with the water.
Birds a little more ambitious than cup-makers build a dome over a cup. At this point, five chapters have been spent on nests largely produced from plant materials, at least the top part. Chapter six is on mud nests, and this image of a cliff swallow colony is one of the most stunning in the book (page 93). Barn swallows build nests that are similar, if more open, but to my observation, are nearly always solitary. It takes hundreds of flights, carrying a small ball of mud in the beak, to build a mud nest. During the carrying, some saliva gets mixed in, which increases the adhesive properties of the mud.
We return to plant materials when we consider hanging nests, which are usually stitched or woven, such as the oriole nest. Orioles and other weaving birds work harder than most others, and it takes a long time, working with only a beak, to weave their elaborate nests. I remember getting a fallen oriole nest, and trying to figure out how the strands were put together. With my ten fingers and the help of tweezers, I was scarcely able to untwine just a strand or two.
Not all woven nests are pendulous, of course. Some look superficially like a cup nest, but are woven of stranded materials such as grass blades and hang together better than the twiggy nests with which we are most familiar. Key to their success is that they give under pressure, so the initial nest just barely fits the clutch of eggs and the sitting parent, but stretches as the chicks grow.
Mound nests may sometimes be rather simple, as the nests of these flamingos (page 109), but some are very large. Some mound-builders fill the middle of the mound with leaves and leaf litter, and bury the eggs within, so that the composting stuff keeps the eggs warm. These birds don't sit on the eggs, and typically abandon them once they are certain the composting temperature is right. Flamingos and others do incubate the eggs by sitting. Many penguin species also make mound nests.
The tenth chapter is on group nests. These cover the gamut of building styles and materials. Their common element is that multiple bird pairs nest, each in its own "apartment", in a large structure built by all the pairs.
Not all structures built by birds are for nesting and caring for young. Bowers and courts are major examples of nestlike structures that a male bird produces to impress females and induce them to mate with him. Males of bowerbirds and their relatives do not care for the young. After mating, a female goes off alone and builds a small cup nest in a hidden location.
The last chapter is half about "edible" nests, the ones used in bird-nest soup, and half about caches of food that certain woodpeckers produce, often by making a "mailbox" of holes in a dead tree trunk and filling the holes with acorns. As to the soup-nests; I can't imagine eating bird spit, which is the only construction material for the "white" swiftlet nest. Yet there is big business in cultivating swiftlets in Indonesia, where special buildings are constructed for the birds to nest in. Chacun à son gout!
The book is lavishly illustrated, and each chapter contains a "blueprint" page, with specifications for typical nests of each type, plus three or more case studies of a few species. While it is enjoyable to read right through, it is also a valuable reference book, and a good companion book to the field guides we use, which have little information on nests.
Tuesday, November 15, 2011
Visual sorting
kw: observations, visual skills, hobbies
I managed to collect all the 50 US State quarters that were produced since 1999, plus the US territory quarters that came out afterwards. When I got a duplicate, I gave it to my wife, and she also kept most of the State quarters she encountered. She has them all in a box, at least until this morning.
She decided to put them in Whitman folders, and asked for my collection to use as a model. Now, there are two ways I can think of to accomplish this task. One is to use preprinted folders that have each state and year, plus P and D mint marks, so there are two each. Then you just go through, coin after coin, and find its spot in the array.
She only wanted the backs shown, and doesn't care about mint marks, so she got blank folders. The second way is then to sort them into years, because there were five quarters minted each year. Then my collection could be used as a model to get each year into the right order. She did it a third way, a way I could not have used.
She spread them all out on the table, face down, and just looked at them for a while. Then she looked at my coins, muttered "Delaware", unerringly picked out the Delaware coin from the array and put it in the first spot in her folder. She continued with New Jersey, and so on. When I asked why she didn't sort them by years first, she told me she was just using the picture on the back of each coin. She could see it better than the year.
Somehow, probably subconsciously, she had spent no more than a couple of minutes looking at the spread of nearly 100 quarters on the tabletop, and sorted the pictures on their backs. Her visual memory really amazed me. No wonder she always wins at MasterMind!
I managed to collect all the 50 US State quarters that were produced since 1999, plus the US territory quarters that came out afterwards. When I got a duplicate, I gave it to my wife, and she also kept most of the State quarters she encountered. She has them all in a box, at least until this morning.
She decided to put them in Whitman folders, and asked for my collection to use as a model. Now, there are two ways I can think of to accomplish this task. One is to use preprinted folders that have each state and year, plus P and D mint marks, so there are two each. Then you just go through, coin after coin, and find its spot in the array.
She only wanted the backs shown, and doesn't care about mint marks, so she got blank folders. The second way is then to sort them into years, because there were five quarters minted each year. Then my collection could be used as a model to get each year into the right order. She did it a third way, a way I could not have used.
She spread them all out on the table, face down, and just looked at them for a while. Then she looked at my coins, muttered "Delaware", unerringly picked out the Delaware coin from the array and put it in the first spot in her folder. She continued with New Jersey, and so on. When I asked why she didn't sort them by years first, she told me she was just using the picture on the back of each coin. She could see it better than the year.
Somehow, probably subconsciously, she had spent no more than a couple of minutes looking at the spread of nearly 100 quarters on the tabletop, and sorted the pictures on their backs. Her visual memory really amazed me. No wonder she always wins at MasterMind!
Monday, November 14, 2011
Blue is good
kw: book reviews, nonfiction, memoirs, textiles, dyes
There are very few natural blue dyestuffs. Of course, these days synthetic dyes are universal, and only a few craftspeople with time on their hands use the old plant-based (or in the case of carmine, insect-based) dyes. The bluest of the blues, and the most time-consuming to use, is indigo. As it happens, indigo is also probably the most time-consuming to research. Catherine E. McKinley spent at least a couple of years doing so, including many months in sub-Saharan Africa. Her travels there, supported by a Fulbright Fellowship, are chronicled in Indigo: In Search of the Color That Seduced the World.
Ms McKinley is half African-American, one of the few black children adopted into a white family. She was well-received in Africa, where there are many of mixed race. Beginning and ending in Ghana, she also visited Togo, Benin, Côte d'Ivoire, Burkina Faso, Niger and Senegal. Early on in Ghana she was invited to "sit a spell" in a shop, where the spell grew into many months, between her goings elsewhere. When she offered to help around the shop, her patroness cajoled her to take it easy, "Your presence is good for business." She also warned her that her desire, even obsession, regarding indigo was bound to be frustrating. It was. She never really got to see the whole process of making the dye and using it. It takes weeks.
A little here, a little there, the author was able to purchase one cloth and another. In the cosmopolitan cities, "Dutch Wax" batik is the main fashion cloth, using synthetic dyes exclusively. She had to go to the hinterlands for most of her research and most purchases. Some of the styles she was able to find are summarized here; all images in this montage are from her collection:
The Levi blue jeans that your great-grandfather or grandfather may have worn were dyed with indigo. More recently, a synthetic version has been used, at least since the time I was born, and probably longer. Synthetic indigo, made from aniline, is chemically a little different from the natural indigo molecule, and does not rub of on your skin. This quality, of indigo dyeing the wearer, is prized among the Tuaregs, the "blue men" of Saharan Africa.
The journeying was, for the author, not just a fact-finding tour but a spiritual and soul-nourishing quest, even a pilgrimage. She was able to visit several famous dyers and, albeit briefly, view the workings of a dyers' guild. As interested as she may have been in the process, it was the cloths themselves that drove her, that were her obsession.
Her adoption was apparently open enough that she knew her black birth mother. Her white grandmother (whether on her natural father's side, or one of her adoptive parents' mothers, I cannot tell) opposed her yearning toward her African roots. That did not stop her. Every root is important, like the four roots of a molar tooth: If one is damaged, the whole tooth is in jeopardy. The author's quest resulted in a new wholeness for her, making her more comfortable with both her blackness and her whiteness. She needed blue to see both.
My own researches have produced conflicting results, whether indigo is chemically identical to woad, the blue dye of the Britons and other ancient Europeans. I think they are probably slightly different, because woad is considered less color-fast than indigo.
I regret that most of us will never see the true colors of indigo. The image above is not quite right, because the range of indigo blues is outside the color gamut of both synthetic dyes and of computer (or TV) monitor phosphors. The deep blue of a Northern winter sky is just the palest of the colors indigo can produce, and its own gamut ranges to near black. I hope textile museums that own indigo-dyed cloths will keep them on display. Here in the U.S., we are unlikely to see genuine indigo anywhere else.
There are very few natural blue dyestuffs. Of course, these days synthetic dyes are universal, and only a few craftspeople with time on their hands use the old plant-based (or in the case of carmine, insect-based) dyes. The bluest of the blues, and the most time-consuming to use, is indigo. As it happens, indigo is also probably the most time-consuming to research. Catherine E. McKinley spent at least a couple of years doing so, including many months in sub-Saharan Africa. Her travels there, supported by a Fulbright Fellowship, are chronicled in Indigo: In Search of the Color That Seduced the World.
Ms McKinley is half African-American, one of the few black children adopted into a white family. She was well-received in Africa, where there are many of mixed race. Beginning and ending in Ghana, she also visited Togo, Benin, Côte d'Ivoire, Burkina Faso, Niger and Senegal. Early on in Ghana she was invited to "sit a spell" in a shop, where the spell grew into many months, between her goings elsewhere. When she offered to help around the shop, her patroness cajoled her to take it easy, "Your presence is good for business." She also warned her that her desire, even obsession, regarding indigo was bound to be frustrating. It was. She never really got to see the whole process of making the dye and using it. It takes weeks.
A little here, a little there, the author was able to purchase one cloth and another. In the cosmopolitan cities, "Dutch Wax" batik is the main fashion cloth, using synthetic dyes exclusively. She had to go to the hinterlands for most of her research and most purchases. Some of the styles she was able to find are summarized here; all images in this montage are from her collection:
The Levi blue jeans that your great-grandfather or grandfather may have worn were dyed with indigo. More recently, a synthetic version has been used, at least since the time I was born, and probably longer. Synthetic indigo, made from aniline, is chemically a little different from the natural indigo molecule, and does not rub of on your skin. This quality, of indigo dyeing the wearer, is prized among the Tuaregs, the "blue men" of Saharan Africa.
The journeying was, for the author, not just a fact-finding tour but a spiritual and soul-nourishing quest, even a pilgrimage. She was able to visit several famous dyers and, albeit briefly, view the workings of a dyers' guild. As interested as she may have been in the process, it was the cloths themselves that drove her, that were her obsession.
Her adoption was apparently open enough that she knew her black birth mother. Her white grandmother (whether on her natural father's side, or one of her adoptive parents' mothers, I cannot tell) opposed her yearning toward her African roots. That did not stop her. Every root is important, like the four roots of a molar tooth: If one is damaged, the whole tooth is in jeopardy. The author's quest resulted in a new wholeness for her, making her more comfortable with both her blackness and her whiteness. She needed blue to see both.
My own researches have produced conflicting results, whether indigo is chemically identical to woad, the blue dye of the Britons and other ancient Europeans. I think they are probably slightly different, because woad is considered less color-fast than indigo.
I regret that most of us will never see the true colors of indigo. The image above is not quite right, because the range of indigo blues is outside the color gamut of both synthetic dyes and of computer (or TV) monitor phosphors. The deep blue of a Northern winter sky is just the palest of the colors indigo can produce, and its own gamut ranges to near black. I hope textile museums that own indigo-dyed cloths will keep them on display. Here in the U.S., we are unlikely to see genuine indigo anywhere else.
Sunday, November 13, 2011
This fairy tale is rather short of fairies
kw: fairy tales, fantasy, popular culture
We watched the first episode of Once Upon a Time on ABC out of curiosity, my wife and I. We have become strangely enamored of the series. I won't belabor the plot here; if you haven't been watching and are curious, click on the link above, where you can watch past episodes.
The show is very well written, by the writers of Lost, in which you were never sure if the protagonists were even alive (spoiler: they weren't). This series presents a different take on favorite fairy tales of our childhood. As children, we loved it when Cinderella has her "happy ever after", and Snow White is awakened by a kiss (Sleeping Beauty, too, in a curious variant on Snow White). When we grew up, most of us never gave it another thought.
Some years ago, I realized that fairy tales and ghost stories and other fantastical childhood tales are really about coming to terms with the world as we find it. Giant-killer stories are about coping with adults when we were tiny; Cinderella and similar stories are about overcoming early handicaps (sometimes with magical help, sometimes not); dragon stories are about learning to control our inner dragons; and tales of defeating trolls and ogres are mostly wish-fulfillment, as they seldom give us genuine skills needed to deal with schoolyard bullies.
The writers of Once have taken a different tack. Their version of childhood classics is edgier, darker. Snow White, a fugitive from the Queen, is a highway robber. Cinderella makes a deal with Rumpelstiltskin, who is surprisingly willing to tell his name (will they bring in the spinning-straw-into-gold story?), after he disposes of her fairy Godmother.
What is really going on here? It seems most of the conventional fairy tales lacked a Trickster, a figure such as Loki (of Norse mythology). Even when one appeared (Rumpelstiltskin), he was tricked in the end and overcome. But we all grew up and found out that happy endings are hard to come by. We don't kill any giants, we become giants and learn the reasons why our parents were so unreasonable, as seen by tiny minds. The trolls and ogres win all the fights, and in the world of work, we find they all have become middle managers who control our yearly progress reviews. And the dragon? Our personal dragon has lost the power to breathe fire, and had its wings clipped. When we do breathe a little fire, we get a stern e-mail from HR demanding we attend "sensitivity training" courses.
In Norse mythology, Loki wins, though at the end, even he is defeated by the Frost Giants. I do anticipate this element informs the ABC series. The strongest wizard, even stronger than the Queen, is Rumpelstiltskin. His mantra matches our experience: There is a price to be paid. Magic doesn't come free.
Let's see, the next episode is scheduled for Nov 27 – ABC will set it aside on the 20th in favor of the Music Awards. That gives us time for just four episodes before Christmas, and since the following Sunday is New Years' day, I reckon four is all that there are. Four episodes to wrap up the tales, defeat the Queen, and – you can bet on it – throw in a twist at the end, such as the Trickster getting away, to set things up for a follow-on season.
We watched the first episode of Once Upon a Time on ABC out of curiosity, my wife and I. We have become strangely enamored of the series. I won't belabor the plot here; if you haven't been watching and are curious, click on the link above, where you can watch past episodes.
The show is very well written, by the writers of Lost, in which you were never sure if the protagonists were even alive (spoiler: they weren't). This series presents a different take on favorite fairy tales of our childhood. As children, we loved it when Cinderella has her "happy ever after", and Snow White is awakened by a kiss (Sleeping Beauty, too, in a curious variant on Snow White). When we grew up, most of us never gave it another thought.
Some years ago, I realized that fairy tales and ghost stories and other fantastical childhood tales are really about coming to terms with the world as we find it. Giant-killer stories are about coping with adults when we were tiny; Cinderella and similar stories are about overcoming early handicaps (sometimes with magical help, sometimes not); dragon stories are about learning to control our inner dragons; and tales of defeating trolls and ogres are mostly wish-fulfillment, as they seldom give us genuine skills needed to deal with schoolyard bullies.
The writers of Once have taken a different tack. Their version of childhood classics is edgier, darker. Snow White, a fugitive from the Queen, is a highway robber. Cinderella makes a deal with Rumpelstiltskin, who is surprisingly willing to tell his name (will they bring in the spinning-straw-into-gold story?), after he disposes of her fairy Godmother.
What is really going on here? It seems most of the conventional fairy tales lacked a Trickster, a figure such as Loki (of Norse mythology). Even when one appeared (Rumpelstiltskin), he was tricked in the end and overcome. But we all grew up and found out that happy endings are hard to come by. We don't kill any giants, we become giants and learn the reasons why our parents were so unreasonable, as seen by tiny minds. The trolls and ogres win all the fights, and in the world of work, we find they all have become middle managers who control our yearly progress reviews. And the dragon? Our personal dragon has lost the power to breathe fire, and had its wings clipped. When we do breathe a little fire, we get a stern e-mail from HR demanding we attend "sensitivity training" courses.
In Norse mythology, Loki wins, though at the end, even he is defeated by the Frost Giants. I do anticipate this element informs the ABC series. The strongest wizard, even stronger than the Queen, is Rumpelstiltskin. His mantra matches our experience: There is a price to be paid. Magic doesn't come free.
Let's see, the next episode is scheduled for Nov 27 – ABC will set it aside on the 20th in favor of the Music Awards. That gives us time for just four episodes before Christmas, and since the following Sunday is New Years' day, I reckon four is all that there are. Four episodes to wrap up the tales, defeat the Queen, and – you can bet on it – throw in a twist at the end, such as the Trickster getting away, to set things up for a follow-on season.
Friday, November 11, 2011
Mister Biv
kw: observations, colors
I am reading a book about the history of Indigo dye, which I'll review in a day or two. Meanwhile, I was thinking about the influence that indigo had on Isaac Newton. While the essential blue dye of the Anglo-Saxons was woad, indigo from India and Africa was becoming better-known. While the two dyes are chemically similar, indigo is longer-lasting, though both run and stain.
Newton enshrined the deep blue of a strong tincture of indigo in his spectrum, leading to the name for the "color man": Roy G. Biv. I suspect if he hadn't had theological reasons to prefer the number seven to the number six, he'd have left indigo off the list.
The other colors are all quite distinct, and seem to have their places in the spectrum. The continuous spectrum image on the left is a rendering intended to appear as much like a natural spectrum as is possible on a monitor screen. The color blocks I placed near it are, in the case of Red, Yellow and Green, pure rgb colors (r, r+g and g), while the color I labeled Indigo is actually the rgb Blue (b).
The "Orange" is r+0.5g, the "Blue" is b+0.5g, and the "Violet" is b+0.5r. It is likely that "Blue" to Newton was even closer to Cyan (b+g), but it is clear he demarcated a range of color very near the spot in the spectrum at which the R cone in the eye has minimum reaction, the purest blues the eye can see, and labeled it Indigo. The purplish look of the violet range is because the R cone has an extra response peak there.
Isaac Newton did pretty well, having as yet no scientific basis for the colorimetry of the normal eye. We can be sure, though, that he had pretty normal (or "ordinary") vision, because had he been color blind or color-anomalous, he'd have been unable to distinguish this many major hues. Now that we know more about color opposition and have more scientific colorimetry available, old Mr. Biv is giving way to RyGcBm, which is pretty hard to render as a name!
I am reading a book about the history of Indigo dye, which I'll review in a day or two. Meanwhile, I was thinking about the influence that indigo had on Isaac Newton. While the essential blue dye of the Anglo-Saxons was woad, indigo from India and Africa was becoming better-known. While the two dyes are chemically similar, indigo is longer-lasting, though both run and stain.
Newton enshrined the deep blue of a strong tincture of indigo in his spectrum, leading to the name for the "color man": Roy G. Biv. I suspect if he hadn't had theological reasons to prefer the number seven to the number six, he'd have left indigo off the list.
The other colors are all quite distinct, and seem to have their places in the spectrum. The continuous spectrum image on the left is a rendering intended to appear as much like a natural spectrum as is possible on a monitor screen. The color blocks I placed near it are, in the case of Red, Yellow and Green, pure rgb colors (r, r+g and g), while the color I labeled Indigo is actually the rgb Blue (b).
The "Orange" is r+0.5g, the "Blue" is b+0.5g, and the "Violet" is b+0.5r. It is likely that "Blue" to Newton was even closer to Cyan (b+g), but it is clear he demarcated a range of color very near the spot in the spectrum at which the R cone in the eye has minimum reaction, the purest blues the eye can see, and labeled it Indigo. The purplish look of the violet range is because the R cone has an extra response peak there.
Isaac Newton did pretty well, having as yet no scientific basis for the colorimetry of the normal eye. We can be sure, though, that he had pretty normal (or "ordinary") vision, because had he been color blind or color-anomalous, he'd have been unable to distinguish this many major hues. Now that we know more about color opposition and have more scientific colorimetry available, old Mr. Biv is giving way to RyGcBm, which is pretty hard to render as a name!
Thursday, November 10, 2011
Six impossible things
kw: book reviews, nonfiction, physics, cosmology
I almost put "fantasy" as a keyword, but we are in a realm that a great many physicists accept as fact. I just finished reading The Grand Design by Stephen Hawking and Leonard Mlodinow. I have enjoyed Dr. Hawking's prior books, and I enjoyed this one. However, it is clear he is preaching a viewpoint, and I came away unconvinced.
Stephen Hawking has been laboring for decades to produce an elegant theory that explains the Universe without any special conditions required. This is understandable. There are dozens of parameters that must be fine-tuned for the Standard Model and quantum theory to "work". For example, there is a resonance in the energy spectrum of the Carbon-12 nucleus; if it were a few percent higher or lower, either the triple alpha process would not work, leading to a helium universe, or the carbon could not further fuse to produce oxygen. Either way, no heavier elements would be produced and there would be no "rocky" planets.
In this book, a Theory of Everything is still an ideal, but the authors throw in the towel and propose instead M-Theory (the reason for "M" is not known). M-Theory is a hodge-podge of all the cosmological theories that work within a certain range of parameters, that also fit together in the ranges where they overlap. In numerical methods we call that a "piecewise continuous" construction, and it is usually a sorry substitute for a complete analytical method.
Last evening the local PBS station showed a double Nova feature: "The Fabric of the Cosmos: The Illusion of Time" and "The Elegant Universe: Einstein's Dream". They covered material similar to that found in The Grand Design, and at one point the narrator (scientist and author Brian Greene) raised the question, "Are we smart enough to understand a theory of everything if we see one?" He answered that most cosmologists believe that we are. I remain skeptical. The Universe already passed through 13.7 billion years without any creatures (that we know of) who understand that there are quanta; it could take a few thousands or millions of years of further evolution before we actually understand them.
At present the foundational quantum theory is the Copenhagen Interpretation. Its basic tenet states that a quantum event does not solidify into an actual quantum being at an actual location until an observation is made. The implication, at least as Niels Bohr understood it, was that such an observation needed to be made by an intelligent observer. Thus, the old saw, "If a tree falls in the forest, does it make a sound?" must be answered, "Of course, not; it doesn't even reach the ground if nobody is there to observe it." This is patent nonsense. Quantum events happen by the quintillions per cubic meter every second, whether anybody is looking or not.
Hawking and Mlodinow never mention the Copenhagen Interpretation, but it underlies several chapters. These illustrate just how desperately scientists avoid saying, "I don't know." For example, it is known that a particle, whether a boson (such as a photon) or fermion (such as an electron or even a molecule), that is moving with a certain velocity, is influenced by objects that it passes "near", and even by objects farther away. It is conjectured that every moving particle is affected by every other particle in the universe. The strength of these effects are very small for objects that are farther "to the side" than one or two deBroglie wavelengths of the particle. But, apparently, never zero, even over light years.
I wonder what kind of experiment we'd have to do to determine whether the effect of a "nearby" object on the flight of an electron is to be evaluated using relativistic or "simultaneous" (that is, classical) mathematics. Could the object be a high-intensity laser beam? Probably; then you could use picosecond switching of such a beam to see when it deflects an electron. Considering that speed-of-light signals move about 30 cm/nsec, this one will take some doing.
Back to the affected particle. We call the scattering of particles into a diverging beam, by their passage through a hole or past an edge, "diffraction". Richard Feynman developed QED (quantum electrodynamics) by proposing that the particle actually took all possible paths between its starting position and its final absorption at some point (perhaps on a screen), and its eventual location was affected by some statistical combination of all that infinity of possible paths. If you actually do the work to add up a great many of the most probable paths, you can make very, very accurate predictions about the statistical results of a large number of quantum events, though you can predict nothing at all about any single event, not even whether it will in actuality happen.
Does a moving particle really take every path before "deciding" on one of them? Someone who says anything other than "I don't know" is just broadcasting ignorance. The all-paths premise is a model, one possible way of deriving the mathematics needed to make statistical predictions. We will most likely develop other models, and it is quite likely that at least one of them will have simpler math than QED.
An alternate model, but one that doesn't allow for mathematical treatment, is the splitting universe. This idea proposes that whenever something affects a particle, the universe splits into as many alternate universes as are needed for every path to be followed, just that each universe gets a different path. Considering that quantum events happen by the quintillions per second per cubic meter, that's a lot of universes.
A different multiple universe theory is based on the fine tuning seen in this one. It is proposed that quantities such as the fine-structure constant or the mass of a neutron can have a range of values, and in different universes all possible values are produced. The only universes that persist are those that have appropriate values that allow such persistence, and of those, only a very small number can support an environment in which life is able to arise and produce cosmologists. This is the anthropic principle (the authors do some arm-waving and show that both the weak and strong anthropic principles, as currently known, are the same thing. Thus I mention only "the" anthropic principle). Simply stated, the universe is the way it is because it had to be so, or we would not be here. Well, yeah, but so what? It is a tautology.
Finally, there is string theory. This was the subject of the second PBS show also. Fortunately on that show there were a few scientists interviewed who asked the obvious question, "Of the great many string theories being proposed, does any one of them predict anything? Can any of them be tested?" The answer is No and No. They are more evidence of a total inability of scientists to admit, "I don't know," and mean it. The phrase I always hear or read regarding a string theory is "What if…".
Everybody is terminally impatient. I mean that literally. Nearly all cases of accidental death are because somebody (usually the dead person) was too impatient to take the time to do something the right way, whether drive to the store or climb a ladder or cross the street. Hundreds of thousands of iatrogenic (doctor caused) deaths result from impatience on the part of the physician, and sometimes of the (soon to die) patient. In this case, we have a situation similar to "artificial intelligence". The term is a moving target, and the "AI techniques" being touted in some software products are quite far from what I would call "intelligent." I get IT geeks mad when I claim that the quickest way to produce true intelligence is to raise your children well and educate them well. Twenty years to produce a probably intelligent young person, versus seventy years and counting, plus billions and billions of dollars spent programming and database-building, and yet there is not one robot that could survive an English 101 college course.
It is the same with cosmological theories. We have to be patient enough to wait a number of generations for a few people to finish their education and who are smart enough to get the insights needed for better theories. I say "a few people" because, unless there had been a community of very smart people around in 1905-1925, Einstein's theories would have got nowhere. Once he had the critical insights, others understood, and the two Relativity theories took over physics.
Some day, cosmologists will look back at the disparity between special relativity and quantum mechanics, and sigh, "If only they had known X!" But it'll take a while before X becomes not just evident, but even possible, for a human brain. With X in hand, M-Theory won't be needed, strings and multiverses and such will be passé, and nobody will mention Copenhagen any more. Until then, we hobble along with what we have.
I almost put "fantasy" as a keyword, but we are in a realm that a great many physicists accept as fact. I just finished reading The Grand Design by Stephen Hawking and Leonard Mlodinow. I have enjoyed Dr. Hawking's prior books, and I enjoyed this one. However, it is clear he is preaching a viewpoint, and I came away unconvinced.
Stephen Hawking has been laboring for decades to produce an elegant theory that explains the Universe without any special conditions required. This is understandable. There are dozens of parameters that must be fine-tuned for the Standard Model and quantum theory to "work". For example, there is a resonance in the energy spectrum of the Carbon-12 nucleus; if it were a few percent higher or lower, either the triple alpha process would not work, leading to a helium universe, or the carbon could not further fuse to produce oxygen. Either way, no heavier elements would be produced and there would be no "rocky" planets.
In this book, a Theory of Everything is still an ideal, but the authors throw in the towel and propose instead M-Theory (the reason for "M" is not known). M-Theory is a hodge-podge of all the cosmological theories that work within a certain range of parameters, that also fit together in the ranges where they overlap. In numerical methods we call that a "piecewise continuous" construction, and it is usually a sorry substitute for a complete analytical method.
Last evening the local PBS station showed a double Nova feature: "The Fabric of the Cosmos: The Illusion of Time" and "The Elegant Universe: Einstein's Dream". They covered material similar to that found in The Grand Design, and at one point the narrator (scientist and author Brian Greene) raised the question, "Are we smart enough to understand a theory of everything if we see one?" He answered that most cosmologists believe that we are. I remain skeptical. The Universe already passed through 13.7 billion years without any creatures (that we know of) who understand that there are quanta; it could take a few thousands or millions of years of further evolution before we actually understand them.
At present the foundational quantum theory is the Copenhagen Interpretation. Its basic tenet states that a quantum event does not solidify into an actual quantum being at an actual location until an observation is made. The implication, at least as Niels Bohr understood it, was that such an observation needed to be made by an intelligent observer. Thus, the old saw, "If a tree falls in the forest, does it make a sound?" must be answered, "Of course, not; it doesn't even reach the ground if nobody is there to observe it." This is patent nonsense. Quantum events happen by the quintillions per cubic meter every second, whether anybody is looking or not.
Hawking and Mlodinow never mention the Copenhagen Interpretation, but it underlies several chapters. These illustrate just how desperately scientists avoid saying, "I don't know." For example, it is known that a particle, whether a boson (such as a photon) or fermion (such as an electron or even a molecule), that is moving with a certain velocity, is influenced by objects that it passes "near", and even by objects farther away. It is conjectured that every moving particle is affected by every other particle in the universe. The strength of these effects are very small for objects that are farther "to the side" than one or two deBroglie wavelengths of the particle. But, apparently, never zero, even over light years.
I wonder what kind of experiment we'd have to do to determine whether the effect of a "nearby" object on the flight of an electron is to be evaluated using relativistic or "simultaneous" (that is, classical) mathematics. Could the object be a high-intensity laser beam? Probably; then you could use picosecond switching of such a beam to see when it deflects an electron. Considering that speed-of-light signals move about 30 cm/nsec, this one will take some doing.
Back to the affected particle. We call the scattering of particles into a diverging beam, by their passage through a hole or past an edge, "diffraction". Richard Feynman developed QED (quantum electrodynamics) by proposing that the particle actually took all possible paths between its starting position and its final absorption at some point (perhaps on a screen), and its eventual location was affected by some statistical combination of all that infinity of possible paths. If you actually do the work to add up a great many of the most probable paths, you can make very, very accurate predictions about the statistical results of a large number of quantum events, though you can predict nothing at all about any single event, not even whether it will in actuality happen.
Does a moving particle really take every path before "deciding" on one of them? Someone who says anything other than "I don't know" is just broadcasting ignorance. The all-paths premise is a model, one possible way of deriving the mathematics needed to make statistical predictions. We will most likely develop other models, and it is quite likely that at least one of them will have simpler math than QED.
An alternate model, but one that doesn't allow for mathematical treatment, is the splitting universe. This idea proposes that whenever something affects a particle, the universe splits into as many alternate universes as are needed for every path to be followed, just that each universe gets a different path. Considering that quantum events happen by the quintillions per second per cubic meter, that's a lot of universes.
A different multiple universe theory is based on the fine tuning seen in this one. It is proposed that quantities such as the fine-structure constant or the mass of a neutron can have a range of values, and in different universes all possible values are produced. The only universes that persist are those that have appropriate values that allow such persistence, and of those, only a very small number can support an environment in which life is able to arise and produce cosmologists. This is the anthropic principle (the authors do some arm-waving and show that both the weak and strong anthropic principles, as currently known, are the same thing. Thus I mention only "the" anthropic principle). Simply stated, the universe is the way it is because it had to be so, or we would not be here. Well, yeah, but so what? It is a tautology.
Finally, there is string theory. This was the subject of the second PBS show also. Fortunately on that show there were a few scientists interviewed who asked the obvious question, "Of the great many string theories being proposed, does any one of them predict anything? Can any of them be tested?" The answer is No and No. They are more evidence of a total inability of scientists to admit, "I don't know," and mean it. The phrase I always hear or read regarding a string theory is "What if…".
Everybody is terminally impatient. I mean that literally. Nearly all cases of accidental death are because somebody (usually the dead person) was too impatient to take the time to do something the right way, whether drive to the store or climb a ladder or cross the street. Hundreds of thousands of iatrogenic (doctor caused) deaths result from impatience on the part of the physician, and sometimes of the (soon to die) patient. In this case, we have a situation similar to "artificial intelligence". The term is a moving target, and the "AI techniques" being touted in some software products are quite far from what I would call "intelligent." I get IT geeks mad when I claim that the quickest way to produce true intelligence is to raise your children well and educate them well. Twenty years to produce a probably intelligent young person, versus seventy years and counting, plus billions and billions of dollars spent programming and database-building, and yet there is not one robot that could survive an English 101 college course.
It is the same with cosmological theories. We have to be patient enough to wait a number of generations for a few people to finish their education and who are smart enough to get the insights needed for better theories. I say "a few people" because, unless there had been a community of very smart people around in 1905-1925, Einstein's theories would have got nowhere. Once he had the critical insights, others understood, and the two Relativity theories took over physics.
Some day, cosmologists will look back at the disparity between special relativity and quantum mechanics, and sigh, "If only they had known X!" But it'll take a while before X becomes not just evident, but even possible, for a human brain. With X in hand, M-Theory won't be needed, strings and multiverses and such will be passé, and nobody will mention Copenhagen any more. Until then, we hobble along with what we have.
Wednesday, November 09, 2011
How blue and how red?
kw: astronomy, stars, colors
Yesterday's post included a frame from a video showing a simulation of a yellow-and-orange double star. I got to wondering how accurate the colors are. Spelunking about on the Web I located Mitchell Charity's Star Colors page, which includes this table:
The colors shown are for the mid-Class stars, O5, B5 and so forth. In particular, an "earlier" O star such as O2 will be a bit bluer than the top row, and a "late" M star such as M8 will be quite a bit closer to red-orange (█), the color of a "red hot" object such as the burner of an electric stove turned all the way up.
Note also that these are the colors we see looking through a telescope, and particularly if we defocus the stars a little so they are colored disks. In other words, these are the colors as seen through the atmosphere. The air in a clear sky scatters about 30% of the light before it reaches the ground, and it scatters nine times as much blue light as red, meaning that the light that comes direct to you has already been reddened by having a lot of the blue removed, but only a little of the redder light. That is why the Sun is considered a yellowish star.
The total light from our sky, particularly on a somewhat overcast day, is the whitest white the eye can see. Our eyes evolved to take maximum advantage of the light our star emits, so that light is, by definition, White. Viewed from outside the atmosphere, any particular star would appear a little bluer than it does from Earth's surface.
This chart shows idealized spectra of stars of a few temperatures, plus the infrared spectrum emitted by a human body (98.6°F = 37.0°C = 310K). 15,000K is the temperature of a mid-Class B star and 3,000K is that of an early M star.
The B star emits three times as much blue as red, while the M star emits almost nine times as much red as blue. But at 3,000K it is still almost 500° hotter than the filament of an incandescent light bulb, which looks white to us when we are indoors. But if you are outside on a cloudy day and see a lighted room through the window, it looks orangeish, just like the "M" row on the table above. That is because your reference for white is now the sky, which is the exact color of the Sun, just spread around by the scattering in the clouds.
Here is a graphic of the appearance of stars of different temperatures, rendered to the same total intensity. I re-drafted the text because the original image used Fahrenheit temperatures. Kelvins are the appropriate units for temperatures higher than a few hundred degrees.
It would take quite a set of neutral density filters to get actual stars of these classes to have such similar intensities. An O star is about a million times as bright as a G star, and a G star is hundreds to thousands of times as bright as an M star.
Most of the bright stars you see in the night sky are B and A, and thus bluish in color. Thus, they "tune" your eyesight to that as the reference white, so when you look at Antares or Betelgeuse, they look quite reddish. In reality, both of those "red" are pale yellowish orange, a thousand degrees hotter and thus somewhat whiter than an incandescent bulb (or a "warm white" CFL).
Finally, this image from Wikimedia Commons gives a better idea of the sizes and colors of Main Sequence stars of the different Classes. O and B stars are called Main Sequence giants and the rest are called dwarfs (The visually brightest star, Sirius, is a dwarf of Class A, though it is almost three times as large as the Sun). Even an O giant, however, is much smaller than a red giant, which is a very expanded main sequence star in the helium-burning stage.
Try this sometime, when you have a telescope available, perhaps at a star party. Look at a rich open cluster such as the Perseus Double Cluster, and then defocus the eyepiece a little so the stars are small disks. Among the mostly whitish dots, a few will be bluer, and several will be yellow or orange. With a little thought (and the table above), you'll be able to estimate the temperature of each star.
Yesterday's post included a frame from a video showing a simulation of a yellow-and-orange double star. I got to wondering how accurate the colors are. Spelunking about on the Web I located Mitchell Charity's Star Colors page, which includes this table:
The colors shown are for the mid-Class stars, O5, B5 and so forth. In particular, an "earlier" O star such as O2 will be a bit bluer than the top row, and a "late" M star such as M8 will be quite a bit closer to red-orange (█), the color of a "red hot" object such as the burner of an electric stove turned all the way up.
Note also that these are the colors we see looking through a telescope, and particularly if we defocus the stars a little so they are colored disks. In other words, these are the colors as seen through the atmosphere. The air in a clear sky scatters about 30% of the light before it reaches the ground, and it scatters nine times as much blue light as red, meaning that the light that comes direct to you has already been reddened by having a lot of the blue removed, but only a little of the redder light. That is why the Sun is considered a yellowish star.
The total light from our sky, particularly on a somewhat overcast day, is the whitest white the eye can see. Our eyes evolved to take maximum advantage of the light our star emits, so that light is, by definition, White. Viewed from outside the atmosphere, any particular star would appear a little bluer than it does from Earth's surface.
This chart shows idealized spectra of stars of a few temperatures, plus the infrared spectrum emitted by a human body (98.6°F = 37.0°C = 310K). 15,000K is the temperature of a mid-Class B star and 3,000K is that of an early M star.
The B star emits three times as much blue as red, while the M star emits almost nine times as much red as blue. But at 3,000K it is still almost 500° hotter than the filament of an incandescent light bulb, which looks white to us when we are indoors. But if you are outside on a cloudy day and see a lighted room through the window, it looks orangeish, just like the "M" row on the table above. That is because your reference for white is now the sky, which is the exact color of the Sun, just spread around by the scattering in the clouds.
Here is a graphic of the appearance of stars of different temperatures, rendered to the same total intensity. I re-drafted the text because the original image used Fahrenheit temperatures. Kelvins are the appropriate units for temperatures higher than a few hundred degrees.
It would take quite a set of neutral density filters to get actual stars of these classes to have such similar intensities. An O star is about a million times as bright as a G star, and a G star is hundreds to thousands of times as bright as an M star.
Most of the bright stars you see in the night sky are B and A, and thus bluish in color. Thus, they "tune" your eyesight to that as the reference white, so when you look at Antares or Betelgeuse, they look quite reddish. In reality, both of those "red" are pale yellowish orange, a thousand degrees hotter and thus somewhat whiter than an incandescent bulb (or a "warm white" CFL).
Finally, this image from Wikimedia Commons gives a better idea of the sizes and colors of Main Sequence stars of the different Classes. O and B stars are called Main Sequence giants and the rest are called dwarfs (The visually brightest star, Sirius, is a dwarf of Class A, though it is almost three times as large as the Sun). Even an O giant, however, is much smaller than a red giant, which is a very expanded main sequence star in the helium-burning stage.
Try this sometime, when you have a telescope available, perhaps at a star party. Look at a rich open cluster such as the Perseus Double Cluster, and then defocus the eyepiece a little so the stars are small disks. Among the mostly whitish dots, a few will be bluer, and several will be yellow or orange. With a little thought (and the table above), you'll be able to estimate the temperature of each star.
Tuesday, November 08, 2011
Double sunsets
kw: astronomy, exoplanets, discoveries
Well! I let this one slip by me. Almost two months ago, September 15, 2011, the Kepler Mission folks announced the discovery of a planet similar in size to Saturn, that is orbiting a double star. In this frame from the NASA animation of the system, the larger yellow star is a K-class dwarf half the size of the Sun, and the smaller orange star is an M-class dwarf. They orbit their common center of mass at a distance of 0.22 AU from one another, while the planet's orbital radius is 0.7 AU, about the distance of Venus from the Sun. If you project from the small star through the large star to the brightest dot about 4x their distance, that's the planet. Of course it is much easier to see in the video, where it is moving rapidly.
There has been much debate among scientists (and science fiction aficionados) whether stable planetary orbits around double stars are possible. This demonstrates that such cases are indeed possible. It remains to be seen whether a planet can orbit stably in a double star system when its orbital radius is similar to the distance between the stars. Speculations about looping orbits have abounded for decades.
Given that, from Earth's perspective, the stars are an eclipsing binary, and that the planet also transits both stars, the planet is treated to frequent eclipses and transits of the two stars, and double sunrises or double sunsets must be common. A dense, Saturn-size object is unlikely to have a surface from which the sky can be seen, so anyone visiting the system will have to watch the sky from the surface of a satellite. Both our Jupiter and Saturn have many satellites, so this planet will likely have several to choose from.
Well! I let this one slip by me. Almost two months ago, September 15, 2011, the Kepler Mission folks announced the discovery of a planet similar in size to Saturn, that is orbiting a double star. In this frame from the NASA animation of the system, the larger yellow star is a K-class dwarf half the size of the Sun, and the smaller orange star is an M-class dwarf. They orbit their common center of mass at a distance of 0.22 AU from one another, while the planet's orbital radius is 0.7 AU, about the distance of Venus from the Sun. If you project from the small star through the large star to the brightest dot about 4x their distance, that's the planet. Of course it is much easier to see in the video, where it is moving rapidly.
There has been much debate among scientists (and science fiction aficionados) whether stable planetary orbits around double stars are possible. This demonstrates that such cases are indeed possible. It remains to be seen whether a planet can orbit stably in a double star system when its orbital radius is similar to the distance between the stars. Speculations about looping orbits have abounded for decades.
Given that, from Earth's perspective, the stars are an eclipsing binary, and that the planet also transits both stars, the planet is treated to frequent eclipses and transits of the two stars, and double sunrises or double sunsets must be common. A dense, Saturn-size object is unlikely to have a surface from which the sky can be seen, so anyone visiting the system will have to watch the sky from the surface of a satellite. Both our Jupiter and Saturn have many satellites, so this planet will likely have several to choose from.
Monday, November 07, 2011
Oh, the thinks they can think
kw: book reviews, nonfiction, science, innovation
Say "Hello" to your weight loss coach, named Autom, but you can name it anything you like. The people who have used one all named it, and became very attached.
This is a recent version of the automated health coach, developed by Cory Kidd of the MIT Media Lab's Personal Robots workshop. In a three-way test, of Autom, of a laptop that accessed the same database Autom uses, and of a dieter's diary (the standard method), Autom won hands-down, and the people using one were all very reluctant to let it go when the day came to return all the robots to the lab.
On average, we can keep to a diet for three or four weeks, so this was a six-week trial. By week four, half the people in the two non-Autom groups had dropped out, and by week six, nearly all had. But those using Autom were almost all continuing their program and loving it. The positive reinforcement of a "social robot", using techniques developed by the most successful human weight loss coaches, make for an unbeatable combination.
This is just one of about two dozen projects highlighted by Frank Moss, former director of the MIT Media Lab, in The Sorcerers and Their Apprentices: How the Digital Magicians of the MIT Media Lab are Creating the Innovative Technologies That Will Transform Our Lives. Each of the book's eight chapters delves into about three technologies or programs, with plenty of historical information to show how "enforced serendipity" and "no-barrier transparency" and other sometimes counter-intuitive principles of the Lab's operation have enabled very rapid conversion of wild ideas into useful products and life-changing programs.
As another example, the Biomechatronics group has not only developed more lifelike artificial limbs, but on the principle that "We are all disabled, just in different ways and to different degrees" (a paraphrase of Sidney Papert), this group is developing exoskeleton components that make it easier to walk in rough terrain, run long distances, or carry heavy loads, and not always with the need for a battery-filled backpack. Sometimes, just by changing the angle of attack a little, a component can reduce the energy needed to take a step or make a movement.
Hugh Herr, the head of the group, is himself a double amputee, but re-crafted his own prostheses years ago. When the author e-mailed him some time ago with a question, the reply came, "Skiing. Will give it attention when down from the mountain."
An effort that seems quite different, but is similar in essence, is the Opera of the Future group, which developed "hyperinstruments" and the Hyperscore program that allow even severely disabled persons to compose and conduct their own works. The program resulted a few years ago in the performance of a work "My Eagle Song", conducted by its composer, wheelchair-bound Dan Ellsey, and that led to his current career as a sought-after public speaker, even though he must speak through a synthesizer, much as Stephen Hawking does.
On a simpler note, Ankit Mohan of the Camera Culture group has produced a handheld device called NETRA that checks your vision. Such devices, if they can be produced for $10 each, could revolutionize eye testing in poor nations. Many cases of functional blindness can be "cured" with a pair of inexpensive spectacles. (By the way, I know how to check nearsightedness with a meter stick, which costs only $1. But the method can't check for astigmatism. Then again, that seldom needs correction.)
Then there is the CityCar, a foldable two-seater developed by the Smart Cities group. Three of these fit into a conventional parking space. Fully electric, they could form the foundation of a one-way-rental business model, such as that used with bicycles or small jitneys in some countries.
A larger issue is to design the city for which CityCar is practical. The car is a result, not a cause. The group began by designing the kind of city in which they would like to live, then designed a car to match. The two key innovations here are the folding design and the Robotic Wheel, in which everything except the battery is packed into a smart hub. In some designs, the wheels can rotate fully, allowing the car to slide sideways into tiny a parking spot. Push a button and in it goes.
The watchword at MIT Media Lab that makes all of this possible is the removal of barriers: barriers between disciplines, barriers of the quarterly budget cycle, barriers of black-hat thinking. "Don't tell me, build one and show me" is the mantra. Every student vetted to work on projects there goes through a mechanical training program in their very sophisticated mechanical shop. For an exercise, one student produced a running wall clock on the 3-D printer: hands, gears, weights, and all. One pass.
For me, a book like this rates 11 on a 10-point scale of coolness. Nobody else is doing curiosity-driven research. At best, researchers are allowed a day or two a month of "blue sky" or "bootleg" time, with the rest devoted to the short-term, product-oriented research that has taken over industrial America. Even longer term programs found at a few places are too product focused to allow much straying into the "why did that happen?" arena.
MIT Media Lab is a place we need, and a host of corporate sponsors agree, keeping it funded and letting researchers collaborate with the professors and their students (the sorcerers and their apprentices). It works.
Say "Hello" to your weight loss coach, named Autom, but you can name it anything you like. The people who have used one all named it, and became very attached.
This is a recent version of the automated health coach, developed by Cory Kidd of the MIT Media Lab's Personal Robots workshop. In a three-way test, of Autom, of a laptop that accessed the same database Autom uses, and of a dieter's diary (the standard method), Autom won hands-down, and the people using one were all very reluctant to let it go when the day came to return all the robots to the lab.
On average, we can keep to a diet for three or four weeks, so this was a six-week trial. By week four, half the people in the two non-Autom groups had dropped out, and by week six, nearly all had. But those using Autom were almost all continuing their program and loving it. The positive reinforcement of a "social robot", using techniques developed by the most successful human weight loss coaches, make for an unbeatable combination.
This is just one of about two dozen projects highlighted by Frank Moss, former director of the MIT Media Lab, in The Sorcerers and Their Apprentices: How the Digital Magicians of the MIT Media Lab are Creating the Innovative Technologies That Will Transform Our Lives. Each of the book's eight chapters delves into about three technologies or programs, with plenty of historical information to show how "enforced serendipity" and "no-barrier transparency" and other sometimes counter-intuitive principles of the Lab's operation have enabled very rapid conversion of wild ideas into useful products and life-changing programs.
As another example, the Biomechatronics group has not only developed more lifelike artificial limbs, but on the principle that "We are all disabled, just in different ways and to different degrees" (a paraphrase of Sidney Papert), this group is developing exoskeleton components that make it easier to walk in rough terrain, run long distances, or carry heavy loads, and not always with the need for a battery-filled backpack. Sometimes, just by changing the angle of attack a little, a component can reduce the energy needed to take a step or make a movement.
Hugh Herr, the head of the group, is himself a double amputee, but re-crafted his own prostheses years ago. When the author e-mailed him some time ago with a question, the reply came, "Skiing. Will give it attention when down from the mountain."
An effort that seems quite different, but is similar in essence, is the Opera of the Future group, which developed "hyperinstruments" and the Hyperscore program that allow even severely disabled persons to compose and conduct their own works. The program resulted a few years ago in the performance of a work "My Eagle Song", conducted by its composer, wheelchair-bound Dan Ellsey, and that led to his current career as a sought-after public speaker, even though he must speak through a synthesizer, much as Stephen Hawking does.
On a simpler note, Ankit Mohan of the Camera Culture group has produced a handheld device called NETRA that checks your vision. Such devices, if they can be produced for $10 each, could revolutionize eye testing in poor nations. Many cases of functional blindness can be "cured" with a pair of inexpensive spectacles. (By the way, I know how to check nearsightedness with a meter stick, which costs only $1. But the method can't check for astigmatism. Then again, that seldom needs correction.)
Then there is the CityCar, a foldable two-seater developed by the Smart Cities group. Three of these fit into a conventional parking space. Fully electric, they could form the foundation of a one-way-rental business model, such as that used with bicycles or small jitneys in some countries.
A larger issue is to design the city for which CityCar is practical. The car is a result, not a cause. The group began by designing the kind of city in which they would like to live, then designed a car to match. The two key innovations here are the folding design and the Robotic Wheel, in which everything except the battery is packed into a smart hub. In some designs, the wheels can rotate fully, allowing the car to slide sideways into tiny a parking spot. Push a button and in it goes.
The watchword at MIT Media Lab that makes all of this possible is the removal of barriers: barriers between disciplines, barriers of the quarterly budget cycle, barriers of black-hat thinking. "Don't tell me, build one and show me" is the mantra. Every student vetted to work on projects there goes through a mechanical training program in their very sophisticated mechanical shop. For an exercise, one student produced a running wall clock on the 3-D printer: hands, gears, weights, and all. One pass.
For me, a book like this rates 11 on a 10-point scale of coolness. Nobody else is doing curiosity-driven research. At best, researchers are allowed a day or two a month of "blue sky" or "bootleg" time, with the rest devoted to the short-term, product-oriented research that has taken over industrial America. Even longer term programs found at a few places are too product focused to allow much straying into the "why did that happen?" arena.
MIT Media Lab is a place we need, and a host of corporate sponsors agree, keeping it funded and letting researchers collaborate with the professors and their students (the sorcerers and their apprentices). It works.
Saturday, November 05, 2011
B'day non-bash
kw: local events, birthdays
My birthday is in a few days, so my wife and I chose today to have a celebratory lunch. Hint: this one is mentioned in a Beatles song.
More than half the time, when we eat out, we go to a buffet, preferably a Chinese buffet. We get what we want, and don't have to contend with a menu. We live closer to Wilmington than to West Chester, and we almost never go into Philadelphia to eat; and while our favorite buffet in West Chester is China Grill, we decided to go the the newest one in Wilmington, called Hibachi Grill and Supreme Sushi Buffet. It is on Hwy 2, half a mile east of Hwy 7, and the nearest landmark is a Kohl's.
The sushi variety is the greatest I have seen. Uniquely (for the nonce) the ID cards note whether the fish, if there is fish, is raw or cooked. I seldom get raw fish (sashimi) sushi in America, but my wife usually prefers it. We both started with a plate of 8-10 pieces of sushi.
For those who might not know, sushi is a way of preparing a large variety of foods with sticky rice and seaweed. Some has fish, some different other meats or shellfish, but only a narrow range of fish varieties are served raw, those that history has shown to be mostly free of parasites. A sashimi chef is specially trained to spot parasites in the sliced fish and remove them. It isn't perfect; we have both had to be de-wormed before. Most sushi also contains vegetable items, and much is only vegetable. There is always sliced, fresh ginger and wasabi (Japanese horseradish sauce) available. I sometimes use wasabi, and usually a bit of soy sauce.
At the Hibachi Grill they have a hibachi chef, but we didn't partake of his services today. We just went around the buffet tables, of which there were four devoted to Chinese dishes and one to things Western kids are more likely to prefer, such as pizza and mac-n-cheese. There is also a table of fruits and similar items, and one of dessert items like small cakes. Finally, there is a freezer with eight varieties of ice cream for hand dipping.
If I recall right, I had sweet-n-sour whitefish, sauteed mushrooms, triple seafood delight (crab, squid and shrimp in butter sauce), a stuffed crab (this was only so-so), and pepper chicken. With the exception noted, they were excellent. I finished off with a little bowl of cookies-n-cream ice cream.
I used to go to buffet places intending to stuff myself silly. Now I go for a few tasty varieties, and it may take me many visits to sample everything that appeals to me. The number of bodies there that were significantly wider than mine (and I am a bit tubby) indicates that many people are still at the stuffing silly stage.
This newest Chinese Buffet restaurant raises the bar for its kin in the area, and the increase in coupons for its competitors shows how they are feeling the heat. For us, it made for a pleasant midday feast.
My birthday is in a few days, so my wife and I chose today to have a celebratory lunch. Hint: this one is mentioned in a Beatles song.
More than half the time, when we eat out, we go to a buffet, preferably a Chinese buffet. We get what we want, and don't have to contend with a menu. We live closer to Wilmington than to West Chester, and we almost never go into Philadelphia to eat; and while our favorite buffet in West Chester is China Grill, we decided to go the the newest one in Wilmington, called Hibachi Grill and Supreme Sushi Buffet. It is on Hwy 2, half a mile east of Hwy 7, and the nearest landmark is a Kohl's.
The sushi variety is the greatest I have seen. Uniquely (for the nonce) the ID cards note whether the fish, if there is fish, is raw or cooked. I seldom get raw fish (sashimi) sushi in America, but my wife usually prefers it. We both started with a plate of 8-10 pieces of sushi.
For those who might not know, sushi is a way of preparing a large variety of foods with sticky rice and seaweed. Some has fish, some different other meats or shellfish, but only a narrow range of fish varieties are served raw, those that history has shown to be mostly free of parasites. A sashimi chef is specially trained to spot parasites in the sliced fish and remove them. It isn't perfect; we have both had to be de-wormed before. Most sushi also contains vegetable items, and much is only vegetable. There is always sliced, fresh ginger and wasabi (Japanese horseradish sauce) available. I sometimes use wasabi, and usually a bit of soy sauce.
At the Hibachi Grill they have a hibachi chef, but we didn't partake of his services today. We just went around the buffet tables, of which there were four devoted to Chinese dishes and one to things Western kids are more likely to prefer, such as pizza and mac-n-cheese. There is also a table of fruits and similar items, and one of dessert items like small cakes. Finally, there is a freezer with eight varieties of ice cream for hand dipping.
If I recall right, I had sweet-n-sour whitefish, sauteed mushrooms, triple seafood delight (crab, squid and shrimp in butter sauce), a stuffed crab (this was only so-so), and pepper chicken. With the exception noted, they were excellent. I finished off with a little bowl of cookies-n-cream ice cream.
I used to go to buffet places intending to stuff myself silly. Now I go for a few tasty varieties, and it may take me many visits to sample everything that appeals to me. The number of bodies there that were significantly wider than mine (and I am a bit tubby) indicates that many people are still at the stuffing silly stage.
This newest Chinese Buffet restaurant raises the bar for its kin in the area, and the increase in coupons for its competitors shows how they are feeling the heat. For us, it made for a pleasant midday feast.
Friday, November 04, 2011
Pink morning sky
kw: observations, photographs, sky
This morning I left for work just before sunrise. I stopped long enough to take a few pictures of the sky, pink from horizon to horizon. This first image, a vertical panorama, shows from the East almost to the zenith.
This second image is of the Western sky. Though I took an image above it, the stitching program couldn't get the two to go together.
A great way to start the day. I was satisfied just to stand and watch it for a few minutes before getting in to the car and starting my workday.
This morning I left for work just before sunrise. I stopped long enough to take a few pictures of the sky, pink from horizon to horizon. This first image, a vertical panorama, shows from the East almost to the zenith.
This second image is of the Western sky. Though I took an image above it, the stitching program couldn't get the two to go together.
A great way to start the day. I was satisfied just to stand and watch it for a few minutes before getting in to the car and starting my workday.
Hiding in our bunkers
kw: risk aversion
I recently watched a PBS program, "Radioactive Wolves" on Nature. 400,000 people were evacuated from Chernobyl after the meltdown there, and an area called "The Zone" will be uninhabitable by humans for tens of thousands of years. I thought, "By what criterion?"
The program showed how wildlife is flourishing there. In just a couple of decades, many buildings have been breached by "the elements" and the way plants and animals are taking over is more instructive than the "Life After People" series on the History Channel. In this environment, radiation levels are hundreds of times as high as "normal" background, and the fur of the wolves would be considered toxic radiative waste. Yet a couple hundred wolves, and countless other creatures, thrive there.
Late in the program there was a moment that got my back up. The scientists are studying colonies of dormice, and it was noted that "abnormalities" were seen at about twice the usual level. Think of it: the Geiger counter is screaming, but most newborn dormice are still unaffected! The narrator said, "This level of birth defects would never be tolerated among humans."
I say, "Why the hell not?" It just exemplifies the wimpification of supposedly civilized humanity. In some parts of the world, there is still the substantial prospect of predation, of people being eaten by a tiger, leopard, bear or crocodile. Among more than half of humanity, many children are dying of diarrhea and infections that the other half can afford to shrug off with modern medicines. Those crowded masses would probably consider a radiation-soaked landscape quite acceptable if they could just be free of the threats of being eaten or killed by infectious disease.
But there is more. We are so cocooned we cannot tolerate risks of any kind. Buying a house entails risk. I recall mortgage rates of 9%, and being happy they weren't higher. I was not as happy with "only" 5% interest on passbook savings, so I invested in CD's that earned 8%. The banks were getting rich on a 1-point spread. Now that mortgage rates are "low" at 4%, the banks only offer 0.2% on passbook savings, and the best CD's are about 1.2%. The banks are crying they aren't making it, with a 3-point spread!
Do you know why X-games and adventure sports have become so popular in Europe, the US and Westernized Asia? Kids have to invent risk, because they don't live it. And do you know what killed the U.S. "manned" space program? Two shuttle disasters. Nobody wants to invest in a replacement, primarily because of the risks. The risk-aversion that would have to be built into the design of a space vehicle makes it completely impractical to design at all. It is actually not hard to design a new shuttle that would be quite a bit safer than the recently-retired ones, but that is not considered good enough these days. It needs to be "failure proof". Can't be done at any price.
Look, if you want to go to the Moon, you have to cross 240,000 miles (385,000 km) of radiation-laced vacuum. You have to quickly punch through the Van Allen radiation belts that surround Earth, just to get the first 10% of the way. Unless you burrow into the surface of the Moon, you're going to get a radiation dose similar to parts of The Zone around Chernobyl. This is the primary reason that the Apollo missions were limited to a week or so. These levels of radiation are the biggest obstacle to sending people to Mars with current technology. They'd have to spend eight months getting there, accumulating a damaging radiation exposure on the way, and eight more months getting home.
I agree such a prospect is daunting. It is unlikely that many people will want to take those kinds of risks. But some will! And people vary in their resistance. Not everyone who gets zapped gets cancer. The main problem on a Mars mission is brain damage from the long-term radiation. So, we need to develop a technology to get there two or three times as fast. How about this for a goal: A technology that can take people to Mars in thirty days! And you send a big bulldozer with them (it would have to be solar powered; there is too little oxygen), so they can dig in and shield themselves from the radiation.
By the way, the radiation in space differs from that in The Zone in this way: It is more penetrating. Radioactive fallout produces lots of alpha, which is stopped by a sheet of paper, and somewhat less beta, which can get into the body a short distance, and much less gamma, which is the most penetrating, being very high-energy x-rays. In space, the primary threat is high energy protons, which can pass right through the body, and are massive enough to kill many of the cells they pass through. They are not alpha, beta or gamma; I call them pi radiation.
Back to The Zone. No exclusion effort can be perfectly vigilant for decade after decade. Not everyone fears radiation's effects. Squatters will likely move into The Zone sometime in the next twenty years or less. Maybe they'll live by poaching the game. Doesn't matter how. They'll find the dangers of living there are less fearsome than somewhere else they have already lived, and accept the risks. It is what people do. Sooner or later, we may find that a group of people have evolved more-than-ordinary resistance to radiation poisoning and radiation-induced cancer. They won't mind the risks that going to Mars entails. They might make great long-term astronauts. Will the bunker denizens of the rest of the world let them go?
I recently watched a PBS program, "Radioactive Wolves" on Nature. 400,000 people were evacuated from Chernobyl after the meltdown there, and an area called "The Zone" will be uninhabitable by humans for tens of thousands of years. I thought, "By what criterion?"
The program showed how wildlife is flourishing there. In just a couple of decades, many buildings have been breached by "the elements" and the way plants and animals are taking over is more instructive than the "Life After People" series on the History Channel. In this environment, radiation levels are hundreds of times as high as "normal" background, and the fur of the wolves would be considered toxic radiative waste. Yet a couple hundred wolves, and countless other creatures, thrive there.
Late in the program there was a moment that got my back up. The scientists are studying colonies of dormice, and it was noted that "abnormalities" were seen at about twice the usual level. Think of it: the Geiger counter is screaming, but most newborn dormice are still unaffected! The narrator said, "This level of birth defects would never be tolerated among humans."
I say, "Why the hell not?" It just exemplifies the wimpification of supposedly civilized humanity. In some parts of the world, there is still the substantial prospect of predation, of people being eaten by a tiger, leopard, bear or crocodile. Among more than half of humanity, many children are dying of diarrhea and infections that the other half can afford to shrug off with modern medicines. Those crowded masses would probably consider a radiation-soaked landscape quite acceptable if they could just be free of the threats of being eaten or killed by infectious disease.
But there is more. We are so cocooned we cannot tolerate risks of any kind. Buying a house entails risk. I recall mortgage rates of 9%, and being happy they weren't higher. I was not as happy with "only" 5% interest on passbook savings, so I invested in CD's that earned 8%. The banks were getting rich on a 1-point spread. Now that mortgage rates are "low" at 4%, the banks only offer 0.2% on passbook savings, and the best CD's are about 1.2%. The banks are crying they aren't making it, with a 3-point spread!
Do you know why X-games and adventure sports have become so popular in Europe, the US and Westernized Asia? Kids have to invent risk, because they don't live it. And do you know what killed the U.S. "manned" space program? Two shuttle disasters. Nobody wants to invest in a replacement, primarily because of the risks. The risk-aversion that would have to be built into the design of a space vehicle makes it completely impractical to design at all. It is actually not hard to design a new shuttle that would be quite a bit safer than the recently-retired ones, but that is not considered good enough these days. It needs to be "failure proof". Can't be done at any price.
Look, if you want to go to the Moon, you have to cross 240,000 miles (385,000 km) of radiation-laced vacuum. You have to quickly punch through the Van Allen radiation belts that surround Earth, just to get the first 10% of the way. Unless you burrow into the surface of the Moon, you're going to get a radiation dose similar to parts of The Zone around Chernobyl. This is the primary reason that the Apollo missions were limited to a week or so. These levels of radiation are the biggest obstacle to sending people to Mars with current technology. They'd have to spend eight months getting there, accumulating a damaging radiation exposure on the way, and eight more months getting home.
I agree such a prospect is daunting. It is unlikely that many people will want to take those kinds of risks. But some will! And people vary in their resistance. Not everyone who gets zapped gets cancer. The main problem on a Mars mission is brain damage from the long-term radiation. So, we need to develop a technology to get there two or three times as fast. How about this for a goal: A technology that can take people to Mars in thirty days! And you send a big bulldozer with them (it would have to be solar powered; there is too little oxygen), so they can dig in and shield themselves from the radiation.
By the way, the radiation in space differs from that in The Zone in this way: It is more penetrating. Radioactive fallout produces lots of alpha, which is stopped by a sheet of paper, and somewhat less beta, which can get into the body a short distance, and much less gamma, which is the most penetrating, being very high-energy x-rays. In space, the primary threat is high energy protons, which can pass right through the body, and are massive enough to kill many of the cells they pass through. They are not alpha, beta or gamma; I call them pi radiation.
Back to The Zone. No exclusion effort can be perfectly vigilant for decade after decade. Not everyone fears radiation's effects. Squatters will likely move into The Zone sometime in the next twenty years or less. Maybe they'll live by poaching the game. Doesn't matter how. They'll find the dangers of living there are less fearsome than somewhere else they have already lived, and accept the risks. It is what people do. Sooner or later, we may find that a group of people have evolved more-than-ordinary resistance to radiation poisoning and radiation-induced cancer. They won't mind the risks that going to Mars entails. They might make great long-term astronauts. Will the bunker denizens of the rest of the world let them go?
Thursday, November 03, 2011
It's only the Moon - your move
kw: book reviews, science fiction, games
I have never been much of a gamer, particularly not role-playing games (RPG's) so it paid little attention to the gaming portrayed in The Moon Maze Game by Larry Niven and Steven Barnes. So why read the book at all? you may ask. I'll read anything by Larry Niven. He is always full of interesting new ideas, and this book doesn't disappoint.
The setting is the Moon, in 2084, and not only is the Moon getting pretty well colonized, so are the L5 point and certain asteroids. Computer power and virtual reality gear are very advanced, making full-surround, live-action gaming affordable. Many effects rely on projected holography, which is still technologically far, far beyond known capabilities…but it makes for a good yarn.
On this future Moon, certain people with tons of money have contracted to convert a domed crater into a gaming arena. One of the gamers is an African prince, and when this becomes known to certain Lunar denizens, a plot is hatched to kidnap him and force his father to abdicate in favor of a democratic government. The actual kidnapping is to be carried out by a band of mercenaries who hire out to do high-profile, high-stakes kidnapping.
There are typically two ways to portray villains. One way is as ciphers with simple motive and unalloyed evil intent, black boxes that churn out evil. Another is as complex personalities made known to us by large sections of stream-of-consciousness, yet also primarily evil. Niven and Barnes take a different tack. There is a little window here and there into the thinking and motivations of the four main perpetrators, but they are portrayed with sufficient sympathy that the reader is torn, not quite willing to hate them properly. The characters of the gamers and others who find themselves embattled by the kidnapping and its aftermath add to the richness of the psychological milieu.
I don't know enough about gaming to have much of an opinion. I assume real gamers will drool over the prospect of full-immersion role play that the book offers. The game setting is a purported sequel to the fiction of H. G. Wells, particularly his Moon and Mars stories: Steampunk on steroids!
I'll leave the plot for the reader to ferret out. A number of Lunar characteristics portrayed show how the authors have thought them through. For example, taking a shower, then waiting for the water to drip off before toweling could take a long, long time. Thus, something like the strigil (a blunt, curved scraping blade used in ancient Rome) is posited to remove most of the water more quickly. The low gravity also allows muscle-powered flight using apparatus much smaller than the Gossamer Condor, and this is taken advantage of at one crucial point. So is brachiation. Tarzan might have swung through the jungle like an ape, but an actual human can only brachiate for a few swings before risking a shoulder separation. On the moon, it is almost easy. A little bit is offered about low-G fighting, but so little is actually known that the authors wisely keep it short.
In spite of my unfamiliarity with the gaming aspects, the authors explain enough (sometimes almost too much) that I could keep up. It is quite a gripping adventure.
Now, I wonder, will we really have a colony on the moon in only another 73 years? It will require another generation to arise with stars in their eyes, a confidence in our ability to conquer any barrier, and a willingness to risk that is presently almost absent among the world's peoples, particularly the American public. About a quarter of the world's population is too comfortable and yet too anxious, while the rest is too poor to imagine big things. If this doesn't change, 2084 will come and go with nobody Moon-side to dome up a crater, fill it with air, and strap on wings.
I have never been much of a gamer, particularly not role-playing games (RPG's) so it paid little attention to the gaming portrayed in The Moon Maze Game by Larry Niven and Steven Barnes. So why read the book at all? you may ask. I'll read anything by Larry Niven. He is always full of interesting new ideas, and this book doesn't disappoint.
The setting is the Moon, in 2084, and not only is the Moon getting pretty well colonized, so are the L5 point and certain asteroids. Computer power and virtual reality gear are very advanced, making full-surround, live-action gaming affordable. Many effects rely on projected holography, which is still technologically far, far beyond known capabilities…but it makes for a good yarn.
On this future Moon, certain people with tons of money have contracted to convert a domed crater into a gaming arena. One of the gamers is an African prince, and when this becomes known to certain Lunar denizens, a plot is hatched to kidnap him and force his father to abdicate in favor of a democratic government. The actual kidnapping is to be carried out by a band of mercenaries who hire out to do high-profile, high-stakes kidnapping.
There are typically two ways to portray villains. One way is as ciphers with simple motive and unalloyed evil intent, black boxes that churn out evil. Another is as complex personalities made known to us by large sections of stream-of-consciousness, yet also primarily evil. Niven and Barnes take a different tack. There is a little window here and there into the thinking and motivations of the four main perpetrators, but they are portrayed with sufficient sympathy that the reader is torn, not quite willing to hate them properly. The characters of the gamers and others who find themselves embattled by the kidnapping and its aftermath add to the richness of the psychological milieu.
I don't know enough about gaming to have much of an opinion. I assume real gamers will drool over the prospect of full-immersion role play that the book offers. The game setting is a purported sequel to the fiction of H. G. Wells, particularly his Moon and Mars stories: Steampunk on steroids!
I'll leave the plot for the reader to ferret out. A number of Lunar characteristics portrayed show how the authors have thought them through. For example, taking a shower, then waiting for the water to drip off before toweling could take a long, long time. Thus, something like the strigil (a blunt, curved scraping blade used in ancient Rome) is posited to remove most of the water more quickly. The low gravity also allows muscle-powered flight using apparatus much smaller than the Gossamer Condor, and this is taken advantage of at one crucial point. So is brachiation. Tarzan might have swung through the jungle like an ape, but an actual human can only brachiate for a few swings before risking a shoulder separation. On the moon, it is almost easy. A little bit is offered about low-G fighting, but so little is actually known that the authors wisely keep it short.
In spite of my unfamiliarity with the gaming aspects, the authors explain enough (sometimes almost too much) that I could keep up. It is quite a gripping adventure.
Now, I wonder, will we really have a colony on the moon in only another 73 years? It will require another generation to arise with stars in their eyes, a confidence in our ability to conquer any barrier, and a willingness to risk that is presently almost absent among the world's peoples, particularly the American public. About a quarter of the world's population is too comfortable and yet too anxious, while the rest is too poor to imagine big things. If this doesn't change, 2084 will come and go with nobody Moon-side to dome up a crater, fill it with air, and strap on wings.
Wednesday, November 02, 2011
Two duct tales
kw: product testing, observations
I have had the ducts cleaned in two houses by two different methods, and they differ quite a lot. I haven't had rotary brush cleaning, which only works well if all the ducts are round. It also requires cutting into the plenum to attach a high-capacity vacuum, and we'll cover that in a moment. Both cleaning methods that we used rely on air blast to dislodge debris in the ducts, but they take quite different approaches: one relies on "air pull", the other on "air push".
At the first house, the operator used a truck-mounted vacuum, lots and lots of large-diameter tubing, and a separate air hose. The process was to take off the faceplate of a register or return duct and let the air pressure hold a faceplate with a large, soft gasket, at the end of the vacuum tube, against the hole. The air hose was inserted through a port in the faceplate. It ended in a foot-long flexible tube with a "pull" nozzle at the end. Such a nozzle has several holes directed backwards, toward the faceplate. When the high-pressure air is turned on, the flexible tube whips around, and the air blasts the loosened debris toward the faceplate and it is carried away to the vacuum on the truck. The backward-directed air blast also makes it easy to get the air hose all the way to the end of the duct. My job was to stand by the plenum and tell him (shout) when the end of the hose arrived. He would then increase the air flow and pull it back out, so each duct had a double going-over.
This method is for aluminum ducts only. The whipping hose with the nozzle is likely to crack or break fiberglass ducts. The only disturbance to the air system is the removal and replacement of faceplates. No cutting into the ductwork is needed.
Ten years later, in the house we presently live in, I had a quite different experience. I believe the cleaning was thoroughly done, but consider the process. The first step was to lug a large-capacity vacuum into my basement, cut a foot-square hole in the plenum, and attach the vacuum. Then, near the end of each duct, the operator drilled an inch-diameter hole into which he put an air hose with a push nozzle. He fed the hose in until it reached the vacuum, then turned on the vacuum and the air and pulled the hose back through the duct. The section of duct between the holes he drilled and the vents was reached by taking off the faceplate and using the air hose to blow debris toward the vacuum.
Once he finished all the supply ducts, the hole in the supply plenum was closed by duct taping the cut-out piece, and the process was repeated with the return air plenum. After that was finished and re-closed, he went around and put a piece of duct tape over each of the holes he'd drilled. This whole process made me rather anxious, and I've thought since that I should have not let it be done, but shopped around until I found someone who used the first method. It is less invasive of the whole system.
As I mentioned, the result was probably about the same, but I am much happier with the "air pull" method.
I have had the ducts cleaned in two houses by two different methods, and they differ quite a lot. I haven't had rotary brush cleaning, which only works well if all the ducts are round. It also requires cutting into the plenum to attach a high-capacity vacuum, and we'll cover that in a moment. Both cleaning methods that we used rely on air blast to dislodge debris in the ducts, but they take quite different approaches: one relies on "air pull", the other on "air push".
At the first house, the operator used a truck-mounted vacuum, lots and lots of large-diameter tubing, and a separate air hose. The process was to take off the faceplate of a register or return duct and let the air pressure hold a faceplate with a large, soft gasket, at the end of the vacuum tube, against the hole. The air hose was inserted through a port in the faceplate. It ended in a foot-long flexible tube with a "pull" nozzle at the end. Such a nozzle has several holes directed backwards, toward the faceplate. When the high-pressure air is turned on, the flexible tube whips around, and the air blasts the loosened debris toward the faceplate and it is carried away to the vacuum on the truck. The backward-directed air blast also makes it easy to get the air hose all the way to the end of the duct. My job was to stand by the plenum and tell him (shout) when the end of the hose arrived. He would then increase the air flow and pull it back out, so each duct had a double going-over.
This method is for aluminum ducts only. The whipping hose with the nozzle is likely to crack or break fiberglass ducts. The only disturbance to the air system is the removal and replacement of faceplates. No cutting into the ductwork is needed.
Ten years later, in the house we presently live in, I had a quite different experience. I believe the cleaning was thoroughly done, but consider the process. The first step was to lug a large-capacity vacuum into my basement, cut a foot-square hole in the plenum, and attach the vacuum. Then, near the end of each duct, the operator drilled an inch-diameter hole into which he put an air hose with a push nozzle. He fed the hose in until it reached the vacuum, then turned on the vacuum and the air and pulled the hose back through the duct. The section of duct between the holes he drilled and the vents was reached by taking off the faceplate and using the air hose to blow debris toward the vacuum.
Once he finished all the supply ducts, the hole in the supply plenum was closed by duct taping the cut-out piece, and the process was repeated with the return air plenum. After that was finished and re-closed, he went around and put a piece of duct tape over each of the holes he'd drilled. This whole process made me rather anxious, and I've thought since that I should have not let it be done, but shopped around until I found someone who used the first method. It is less invasive of the whole system.
As I mentioned, the result was probably about the same, but I am much happier with the "air pull" method.