Noise is about more than loudness

 kw: book reviews, nonfiction, science, sound, noise, soundscapes

For about ten years I have worked part time at the Delaware Museum of Natural History (renamed in 2022 the Delaware Museum of Nature and Science). My "office" is on the top floor, above an exhibit hall. During the times the museum is open to the public, I constantly hear the sounds of children talking and shouting in the hall below. I happen to like it. Happy sounds are good sounds. On occasion I venture downstairs to wander among the exhibits. There, the sound is much louder, particularly where there is an exciting exhibit in that exhibit hall. The sound is equally happy, but at that volume, it soon gets tiring and I go back upstairs.

I haven't measured the sound level at the museum—I only recently downloaded an SPL (Sound Pressure Level)  app—but I estimate that the loudness at my desk is about 65-70 dba, about as loud as an older washing machine. Down in the hall, it must be 80 dba or more, with peaks in the 90's…there is nothing quite like a surprised child's shriek!

Near a busy highway, the loudness is also in the 70 dba range, but it is definitely not a happy sound, unless you happen to be a tire salesman and the sounds of tires wearing out leads you to anticipate future tire sales. Few of us treasure the noisy clangor of a busy city street. We go where we must, but when we have a choice, we prefer sounds that are more pleasant, and, importantly, less loud.

The coupled measures of loudness and pleasantness are teased apart for us in Clamor: How Noise Took Over the World and How We Can Take it Back by Chris Berdik.

A definition for those needing it: "dba" means "A-weighted decibels". It is a measure of the intensity of sound, with zero set at the threshold of human hearing. "A-weighting" adjusts the sensitivity at different frequencies to match our ears' sensitivity. The scale is logarithmic, so that an increase of 10 dba means a tenfold increase in sound intensity. Most people consider a 10 dba increase to be "twice as loud," because our senses also follow a logarithmic response.

The app I used to measure sounds after I began reading the book is "SPL Meter" by Keuwlsoft. When installed, it arrives uncalibrated, and I could tell it was reading quite high. I don't have a sonic reference, so to reach an approximate calibration I used several well-reported sounds to set the calibration. Now its readings are about 15 dba lower than before and they accord well with reported measurements. I went around during the past week gathering measurements. I'll discuss a few of these below. The reading shown in this image measures the loudness of a particularly low-flying jet aircraft as measured in my front yard.

The book chronicles the very gradual development of public policy regarding noise. The sonic environment has been ignored almost universally, perhaps with the exception of some of those who plan parks and open spaces such as Central Park in New York City. Central Park is big enough to keep the city's traffic sounds at bay, and many sheltered areas are quiet and restful. Even more so, the gentle forest sounds are soothing, quite in contrast to the typically jangly background noise of a city.

The author's aim is not to add another tome to those extolling quietness and denigrating loudness; rather, his interest is the quality of the sounds that envelop us. Many of us greatly enjoy attending concerts, where the louder sounds threaten to damage our ears; this is more so at a rock concert than at an orchestral concert. But, I have attended an outdoor concert of 1812 Overture by Tchaikovsky that used real cannons. There, it was worthwhile to put one's fingers in one's ears whenever the conductor pointed at the cannons! As fun as that was, I don't listen to loud orchestral music all day long. One of my relatives was a rock drummer for a while and has significant hearing loss. I am a folk singer; we don't go for volume, but for lyrics that touch the soul.

Let's consider: what could make the sounds of a city less stressful? Nearly half of Clamor is about that, about the researchers and companies that design soundscapes. The idea of a soundscape is not to just subtract unpleasant sounds, but also to mix in more pleasant sounds.

Here is my own soundscape practice: As I hinted above, jets fly over our house from time to time. Our neighborhood is in line with one of the runways at Philadelphia Airport, and when the wind is right, the landing pattern has jets sweeping in from all directions to a spot about a mile west of our house, then making a descending beeline for the runway. Most of them are still about a mile high when they cross over, and I've recently measured their sound intensity to be 75 dba. Most of the jets are either a Boeing 737 or an Airbus A320. When a larger plane passes over, not only is it intrinsically louder, but it is usually lower, producing the louder sound recorded above. 80 dba is as loud as my lawn mower, heard from 2 meters away (where my ears are during use). Inside the house, where the background sound level is 24 dba (just a bit louder than a whisper), a jet flying over registers 48 dba, except the big ones exceed 52 dba. Sometimes I take an early afternoon nap. Since 40 dba is generally considered loud enough to disturb sleep, I do this: I turn on the clock radio and reduce the volume until I can't understand the words, but the gentle susurrus of human voices is a kind of white noise that helps me "not hear" the jets when they fly over. My nap is better as a result. The Internet is full of suggestions for private soundscapes: little fountains, audio files of forest sound, playlists of gentle string music, etc., etc.

What is a good soundscape for an office? What do you want to be hearing as you work? What, if anything, should be the background sound for a business meeting, particularly for hard negotiations? All these are being studied. Some progress is being made. Several chapters deal with various aspects of such work.

It's very important to understand that people are hugely various. In the realm of felt experience, "diversity" is much more than ethnicity. Not everyone enjoys the sounds of happy children; some people find it excessively annoying. Most people I know enjoy rock music. There are a very few rock musicians and composers whose work I appreciate; I hate most of it. I like classical music, almost exclusively pre-1900; "12-tone" and "atonal" compositions are just meaningless noise to me. I like country and folk music, but mostly for the lyrics. I like the sounds of a babbling brook in a quiet forest, as seen in this picture, taken in a small woods near our house. Many people would find it either annoying or boring. The sound intensity in this woods is as low as 50 dba, which is "quiet" as defined by urban planners.

I did the following measurements this past week:

• 48 dba outside my front door in the daytime. Most of the sound I could hear was road noise from a highway 1/3 mile (~550 m) away.
• 65 dba from the same spot, when my neighbor across the street accidentally set off his car alarm. Fortuitous timing! The sound is designed to be annoying, to get attention. Most of us have learned to tune it out, making car alarms largely useless.
• 65 dba (ranging from 62-74) seated with friends in a restaurant that doesn't play background music. The higher reading was during conversation at our table.
• 50 dba in the forest as noted above, but...
• 60 dba when crows were calling nearby.
• 82 dba, my lawnmower at 1 meter.
• 79 dba, my lawnmower at 2 meters. Note: a difference of -3 dba indicates the intensity was one-half. Power is proportional to the square of intensity, so this follows the inverse square law: -3 dba is one-fourth of the sound power.
• 64 dba is conversation in an otherwise quiet room. Note that we spoke louder in the restaurant setting.

Clamor comes along at the cusp of a revolution in architecture, city planning, and numerous disciplines that have historically ignored sound. The book is not prescriptive; it is reporting on progress as it happens. I hope in just a few years to find that the sonic environment is more and more taken into account everywhere. I am fortunate to live in a quiet suburb. May those living with more noise soon find that the sounds around them are changing to reduce stress rather than enhance it.

A star in a circle in Nevada

 kw: photo essays, investigations, maps, satellite photographs

It is interesting to peruse odd things people post about what they've seen on Google Maps or Google Earth. Recently I saw a few items that include these coordinates: 37°24'05.7"N, 116°52'06.1"W, which are easier to enter into GEarth (which I used) or GMaps as 37.40158, -116.86781. When you do, this appears:

Note, the accuracy of the coordinates with degrees-minutes-seconds, in tenths of a second, is just over 3 meters or 10 feet. The accuracy of coordinates with decimal degrees, reported to five digits after the decimal point, is 1.1 meters or 3.6 feet. I converted the one to the other, and the fifth decimal is effectively a guard digit, having excess precision.

What is this circle-star figure in the Nevada desert? Spoiler alert, if you want to call it that: I still don't know. This is a report of a journey that hasn't reached the destination. The outer circle is 242.5 m (796 ft) in diameter. The inner circle is less regular, and is about 150 m (490 ft) across. The figure is not really very large.

I first looked back in time, which is why I did this in Google Earth. The earliest clear satellite photo is from 2003, where it appears that some recent activity had taken place:

I shifted the view a little when making this screen capture, to show a series of small craters in the desert floor to the east of the figure. The craters are about 10 m (~34 ft) in diameter. I'll return to them in a moment.

The six squares in the six triangles each contain some darkish object. In 2003, which is less clear, they look like they may be battle tanks. This closeup of the area in 2022 shows something quite different:

Three of the items are seen. They look like missiles. I can't even guess about the object at the center of the figure. This is the sharpest image available at present. I wonder what the missiles are defending?

The 10 meter craters are probably bomb craters. They are much too small to represent nuclear munitions. This image shows craters from fission bomb tests in the 1950's at the Nevada Test Site (as it was popularly called):

This image has the same scale as the prior two. The central blast-exit holes are much larger than 10 m, and the collapse craters are in the 100-150 m range. Here is an overview of a 7x10 km portion of the Nevada Test Site as it appears today:

This area is about 80 km (50 mi) SSE of the circle-star figure we are looking at. The Test Site is in an area now administered by the Dept. of Energy, while our figure is in the middle of the Tonopah Test Range. Both are portions of the Nellis Air Force Range Complex, and entirely surrounded by BLM lands.

I would say that our figure is in a pole of inaccessibility. I decided to look nearby for more clues. About 2.5 km (~1.5 mi) to the west we find an interesting complex:

This image from 2022 shows three walled areas. What look like structures are really various things. The block to the left appears to contain ammunition dumps. The brown square inside a small walled area at lower center seems to be a very old metal building with holes in the roof. What look like small buildings to the right and upper center are mostly various assemblages of shipping containers. Note the black shadows of some kinds of pillars at the corners and midpoints of the walls around two of the sections. Based on a visit I made to a Minuteman missile silo I made many years ago, I surmise that these are motion detectors. I looked back into time:

The images are dated. The earliest one that is somewhat clear is from 2003. The image from 1985 (Landsat, which was the epitome of high resolution at the time!), shows at least that the complex was there already. I suspect it dates from the 1950s. The pillars are seen in the 2014 image, not before. Each image shows a different arrangement of shipping containers. The ammunition bunkers, if that is what they are, appeared after 2014 and before 2020 (which I didn't show here). The square brown thing also appeared after 2014. That's all I can extract from these images at this resolution.

Another area about 3 km (~2 mi) NNE of our figure looks like an early layout for the roads of a suburb:

The area of this image is 3.5x5 km. I included the circle-star so we can see how close it is. The dark spots along cross-shaped portion midway along the connecting road may look like dwellings at this scale, but they are really arrangements of shipping containers.

For this area also I looked into the past. I went back until the "roads" looked fresh, in 2006. The prior year, they are not present at all:

The option that comes to mind is the intention to build a fake suburb to blow up with a nuclear bomb, such as was done elsewhere; a video about one is here. The atmospheric test ban treaty (1963) would have put an end to it.

Earlier I called this area a "pole of inaccessibility." When you enter the coordinates of this point into Google Maps, it is labeled Pahrump, Nevada. However, the actual town of Pahrump is 150 km (93 mi) to the NNE. The nearest paved highway is US 95 (quite different from I-95 along the east coast), about 20 km (12 mi) to the SW. I could find no roads of any kind connecting US 95 to the dirt roads in this area.

Some dirt roads go north, but not in any straightforward way. A broad valley between this area and US 6 some 75-80 km (47-50 mi) to the north is crisscrossed by ephemeral dirt roads. US 6 goes between Tonopah and the real Pahrump, and further to the NE. In other directions, the picture is the same. I suspect the only way to get "here" is by helicopter…unless you walk, and can carry about ten gallons of drinking water. Even in winter the dry Nevada air will suck at least a gallon per day out of you; been there, done that.

Searching out roads to the north I encountered this (the area is about 10x16 km, or 7x10 mi):

Near the center of the concentric circular arcs is a hiking area called "Nye's Giant Target" on Google Maps; it has the sublabel "(small)". This image is from 2012, when the lines were clearer; they have suffered wear through time. Maybe this is a desert version of a crop circle…

There you have it. My speculations, or rather semi-educated guesses. There's no solution to these mysteries outside of military records that have probably been almost forgotten. It is simply fun to traipse around—virtually—to see what is out there.

A multiplanet enthusiast

 kw: book reviews, nonfiction, emigration, planets, mars

From time to time I use a very small prompt with an art generation program. The prompt for this image was "Planets everywhere." The site I used was Leonardo AI with the Lightning engine and its Dynamic style. The engine clearly doesn't understand either physics or astronomy. Actually, the way these programs work, the engine cannot be said to "understand" at all. But I like the surreal look of the image.

I produced this image about a year ago. It came to mind when I saw the cover art for Out of This World and Into the Next: A Physicist's Guide to Space Exploration by Adriana Marais. The author is based in South Africa, and she was one of the Mars One candidates for their plans to send people on a one-way trip. Mars One went out of business in 2019, but the banner has been taken up by Elon Musk and SpaceX.

The book is rather big; it's intended to be comprehensive, a sort of "History of humanity starting from the Big Bang." In keeping with the author's Germanic heritage, the Table of Contents is a thorough outline. Denying the trace of Teutonic detail-mindedness found in my own heritage, I'll touch a few items of interest and leave the rest to the interested reader.

The subjects of Part I, "Where do we come from?", remind me of a Bible verse. The three subjects (elaborated in 13 subchapters) are "The Universe", "Our biosphere", and "Are we alone?" Zechariah 12:1 tells that God "stretched out the heavens, laid the foundations of the earth, and formed the spirit of man within him." Each set of 4-5 items goes from broad to narrow. The tip of the arrow at the end of this Part introduces the Kardashev Scale. This is worth a bit of discussion.

Nikolai Kardashev proposed a three-point scale to describe the energy made available to a technological civilization:

1. A Type 1 civilization, labeled Planetary, has attained control of all the energy available on a single planet, including all the incident sunlight.
2. A Type 2 civilization, labeled Stellar, captures and uses all the energy output of one star, presumably its home star.
3. A Type 3 civilization, labeled Galactic, controls all the energy of its home galaxy.

Many, myself included, add Type 0, to represent the beginning of technology as evidenced by the first mastery of fire. This level was apparently achieved before Homo sapiens arrived on the scene, as much as two million years ago. How far have humans come towards becoming a full Type 1 civilization? Relevant facts:

• Worldwide energy use is about 625 exajoules per year (note: 80% is fossil fuel use). That's 174 billion megawatt-hours (MWh, = 1,000 kWh) per year.
• Solar energy influx is 1.53 million billion MWh per year. The ratio of these two numbers is about 1:8,800. In other words, our global energy use is 0.0114% of the energy available in sunlight.
• Internal heat flow of the earth, half radiogenic and half primordial, is 410 billion MWh per year. Thus total geothermal energy is about 2.4 times the global energy budget.

Thus we are about 1/90th of a percent along the way to being a Kardashev Type 1 civilization. Dr. Marais points out that photosynthesis converts just under 2% of sunlight into sugar, putting the biosphere's Kardashev level about ninety times farther along, compared with vaunted human technology.

Years ago I first examined the "carbon debt" indicated by the oxygen in the atmosphere and the oxidized iron in Earth's crust. Going back to the origin of oxygen-emitting photosynthesis (which came along half a billion to a billion years after other varieties of photosynthesis such that found in sulfur-digesting bacteria), we first find about a billion years of accumulation of "red beds" and other iron oxide deposits. Once the iron was all oxidized, oxygen began to accumulate in the atmosphere, as carbon-containing detritus was buried in the crust and later subducted beneath it by plate tectonics. I concluded that if we could find all the oil, natural gas, coal and tar in the crust, and also the graphite and diamond in the upper mantle, and burn it, that might use up most of the oxygen in the atmosphere. By contrast, 200+ years of fossil fuel consumption have "used up" about 0.01% of it. 

A little thought is sufficient to realize that there are limits to the energy available from fossil fuels, and not just because the oxygen will run out (to be replaced by carbon dioxide). Rather, we must consider the medical fact that humans (and who knows how many other animals) begin to feel distressed when the amount of carbon dioxide in the atmosphere exceeds 1,000 ppm. So, we don't want to go anywhere near that! From the vantage point of 430 ppm today, up from 280 ppm prior to the Industrial Revolution, 1,000 ppm seems far, far off. It isn't. Global energy use is still increasing, fast. Think about that.

A final point. I have seen it proclaimed that human civilization today is approaching a Kardashev level of 1; estimates range up to 0.7. Hmph! We are far below that. Just focusing on Kardashev levels zero and 1, we can consider a logarithmic scale, so that a scale value of 0.7 would represent energy use of about half of total solar input, or 765 quadrillion kWh per year. That's about 4,400 times as much energy as we are presently using! We need a different scale for energy consumption less than 0.1 of the solar value (the logarithm of 0.1 is -1, and starting from 1 for "1 solar output", the result is a Kardashev level of 0). For the moment, I'll set this aside.

As for levels 2 and 3, I have a couple of thoughts. A spherical construction that encloses the entire Sun at a suitable distance (probably between Earth and Mars) could capture all of the Sun's energy. Such a construction is called a Dyson Sphere, after the physicist who popularized the concept. We would need to take apart at least all of Jupiter and possibly Saturn also to accomplish it. Communication is a bit of a problem; the travel time of light or radio across the sphere would take about twenty minutes, one-way. Communication in a Galactic civilization is another thing entirely; getting a signal across the Milky Way Galaxy would require about 100,000 years. Talking across dwarf galaxies such as the Magellanic Clouds would be quicker; only a few thousand years!

In Part II, "Who are we?", the focus at the culmination of the 15 chapters is Terraforming. The next-to-last topic is "The Anthropocene," a designation that some have proposed for a geologic age that began 250-300 years ago with the Industrial Revolution, and so far has resulted in the extinction of many species (though it is so far probably less than one percent). Can we indeed terraform Mars? Let us contrast this with our current activities, which could be considered "the anti-terraforming of Earth" (my coinage).

It is worthwhile to ask, does our experience of human nature give us any grounds for optimism that we can properly terraform another planet? It is wise at this point to jump to the conclusion in Part III (Where are we going?), its last section, "Transforming our world." That is the crux of the matter. Can we terraform Earth? This is a question asked by astrophysicist Neil deGrasse Tyson: Which will cost less, establishing one (or a few) million people in a new colony on Mars, or restoring the environment on Earth so that future global catastrophes will not wipe us off the planet? Clearly, he is in favor of the latter course, and I agree.

I hope Dr. Marais gets her chance to go to Mars. She wants it so much she can taste it. Her evocative essay "Off-World" almost gives us the taste for it. It is markedly utopian. She needs to add to her scientific perspective the lens of history. No utopian society has ever succeeded. The advice of a pioneer of space inhabitation, "Go with friends!", tells you only part of what you need to know. Because friends change. Those who once ran together grow apart. The current divorce rate of about 50% does not bode well for the ability of mere humans to establish the kind of society she describes.

I like the dream. I wish I could conclude it won't turn into a nightmare.

Preparing to write this, I ran the prompt "Planets everywhere" in OpenArt's DynaVision engine, with AI Enhancement turned on. This was the result. The physics is a little better, but this is still surreal. If you were to see this density of planets in the sky, it would be best to go far away. The chaotic gravitational regime would soon prove catastrophic. Still, it's a fun image.

===============

A couple of minor errata:

• On p. 188 Yuri Gagarin is said to have "experience[d] the weightlessness of being beyond Earth's gravitational field." Not even close. He was well within it, but orbiting such that the centripetal force and the gravitational force exactly canceled. He experienced microgravity. If he'd been paying attention, he might have noticed very slight tidal forces tending to reorient him if he tried to float free inside his capsule.
• On p. 195 we read that the wavelengths of visible light are "similar to the size of atoms". The wavelength range of visible light is 400 nm to 700 nm, or roughly half a micrometer. The diameter of a typical atom is 2-3 tenths of a nanometer, or some 2,000 times smaller. The author is making the point that light bounces off material stuff. Actually, X-rays of the sort used in medicine do have wavelengths similar to the size of atoms, and they pass right through most materials. So the physics is wrong anyway.

Who do I think I am?

 kw: book reviews, nonfiction, linguistics, pronouns, popular culture

Toddlers are addressed by everyone as "you" so frequently that they think their name is "You," and upon hearing others using "I" for themselves, the little ones think that "I" and "Me" refer exclusively to those others. Pronouns take a while to get used to. This kind of confusion underlies a bit of wordplay in a Looney Tunes cartoon in which Elmer Fudd is pursuing Bugs Bunny and Daffy Duck. As John McWhorter tells us in the Introduction to his new book, his title is found in this exchange:

BUGS (to Elmer): Would you like to shoot me now or wait till you get home?

DAFFY: Shoot him now, shoot him now.

BUGS: You keep out of this; he doesn't have to shoot you now.

DAFFY: Ha! Hold it right there! Pronoun trouble! It's not, "He doesn't have to shoot 'you' now," it's "He doesn't have to shoot 'me' now." Well, I say he does have to shoot me now! So shoot me now!

(BLAM!) [This being a cartoon, Daffy is now covered in soot]

The title of the book is Pronoun Trouble: The Story of Us in Seven Little Words.

While the author points out the confusion of Daffy in mixing up "me" and "you", the reply of Bugs to Daffy in the third line shows that Bugs isn't so clear himself. The wordplay is reminiscent of the "Who's on First?" routines of the 1930's made famous by Abbott and Costello in the 1940's and later.

As the thread of the book winds along, we find that pronouns have been alternately steadfast and malleable. Each chapter traces the usage of a pronoun or a set of subject-object pronouns (such as "I" and "me" or "he" and "him"). A particularly long section traces the history of "me" as it switched between object-only, subject-only, and a little bit of both. For example, while I was taught that the "correct" way to refer to myself plus a friend doing something is, "Jerry and I went to a movie," for a century or so this has stood alongside "Me and Jerry went…" and almost as frequently, "Jerry and me went…"

Here are the rules I was taught, to which I habitually adhere, going on 70 years:

• When listing a group that includes you, out of modesty refer to yourself last.
• If the group is the subject of the sentence, refer to yourself as "I", as in "I went": "Jerry and I went."
• If the group is the object, refer to yourself as "me", as in "It made me happy": "It made Jerry and me happy."

Period. Those who used alternative constructions were considered ignorant or uneducated and, in a school setting, were firmly corrected. Again and again if necessary.

I admit to a bit of discomfort with accepting Dr. McWhorter's contention that "Me and Jerry went" is permissible due to historical English usage, and even the more, numerous languages that either have dual-use pronouns or don't have object-subject distinctions anyway. I don't really care what is acceptable in Tagalog or !Kung. I want to be clearly understood by Anglophones.

By the end of that first chapter I had a side thought, "I wonder if his goal is to support the singularizing of 'they'?" A quick look at the Table of Contents confirmed my suspicion: the last chapter's title is "They Was Plural." However, I didn't let that slow me down. I enjoyed the book, the linguistic histories and odd collections of pronouns that surround and underlie the ones with which we English speakers fill our prose. I didn't know before that in Old English, the male, female, and neuter third-person singular pronouns were "he", "heo", and "hit". "He" has stuck with us, while over time "hit" was de-aspirated to "it", but the path from "heo" to "she" (with a side jaunt to spit out "her") was more circuitous.

By the way, this puts paid to the contention that pronouns are so pervasive that making changes is arduous-to-impossible. All to support the tiny smattering of folks who don't like being either "he" or "she", and of course it is barbarous to call them "it", so of course "they" is called in to fill the gap. Behind all that is the delusion that "nonbinary" is a valid gender. In actuality, there is tremendous political force behind the delusion, for totalitarian reasons I'll defer for the nonce, such that a change has already been made, and is being forced on an unwilling public. For my part, if someone points to a individual person and says something like, "They are with me," I'm likely to respond, "Is there a mouse in his (or her) pocket?"—depending on the visible appearance of the person. And to close the loop, I have yet to hear someone say, "They is with me." I wonder if the "they" standing by even notices the gaffe.

Furthermore, there are numerous instances of "they" as a nonspecific singular pronoun, such as, "When a newcomer arrives, they need to be greeted by an usher." However, these have arisen over the past 50-60 years primarily by folks who bend over backwards to cater to old-line feminism and its crusade to change "chairman" and "chairwoman" to "chair" or "chairperson", etc. Until I was in my twenties, the acceptable usage was, "When a newcomer arrives, he needs to be greeted by an usher," unless the newcomer is expected to be female, such as at a League of Women Voters event; then, "…she needs…" is preferred.

I would say it is a little early to take up the cudgels for settling on "they" where "it" will work. To the contention that "it" refers to inanimate things, just ask anyone with a pet, where "it" is frequently used to refer to one's furbaby, except by those who over-humanize their pets. So if a man or woman doesn't want to be referred to either by "he" or "she", I'd prefer to say "it". Of course, speaking to such a person, I'll use "you." Just like I would to any other human. Or even a pet.

Not to leave too sour a taste in your mouth, dear reader, I must say that Dr. McWhorter writes very well, the book is quite valuable, and if it proves to be a trend-setter, perhaps I'll have to bend to what then becomes truly common usage. I come from a long-lived family, so I say, time will tell. Who knows what another decade or two will bring.

Spiders aroar - AI training?

kw: blogs, blogging, spider scanning, AI training

About two months ago, July 16, the number of views this blog experienced was 77. That is "about right", historically. For the last six months, that was the closest to a "normal" day; no other day has seen fewer than 200 views, and the rate has frequently been in the thousands per day.

Firstly, here we see the past 24 hours (from Noon 9/4/25 to Noon today):

Even the "dull roar" of the first 14 hours of this record (~100/h) exceeds the July 16 (~3/h) rate by a factor of 30, and the rate since then has been has high as 540/h. World distribution for this period is interesting, and a bit surprising:

Surprise #1: The US is at the top; its total slightly exceeds the combined total for Singapore and Hong Kong.

Surprise #2: The top six countries each exceed 77 views per day, and "other" represents a rate that would hit every post in this blog over less than five days.

Let's look at the past month:

The daily rate on August 20 was around 500 views that day. All others were greater. Switching to the other end of the time scale, here is the "Now" picture, the past two hours:

The "clutter" through most of this period is 3-5 views per minute, never less than 2. That comes to around 3,000 per day. The five spikes in the 40-90 view/min range add another 300 or so views, making up more than half the 595 total for this two-hour period. 595 views/2h = 7,140/day. Probably half of that is in such spikes, the rest as ongoing "clutter". For reference, 77 views/day comes to ~6.4/2h, or 0.053 views/min.

I like to think I am truthful and mostly correct. I hope that is a positive influence for the AI agents that are probably being trained with material from this blog. Considering that there are close to two million blogs more popular than this one (in ordinary times, at least), my influence is likely in the range of 0.00001%. Ha!

Fluorescence on the porch

 kw: photo essays, fluorescence, ultraviolet, spectra, diffraction gratings

This is a look into a bag of plastic rings taken from cottage cheese containers, illuminated with a UV "party light", or "black light". A number of food products are sold with such rings sealing the tops. They are polypropylene, which is not fluorescent by itself; manufacturers add a fluorescent tracer for reasons known only to them.

I happened upon this when I saw a glint of blue on a sunny day, in the grass near a Dunkin Donuts shop. It turned out to be a piece of plastic from a soup container. Later I found that the plastic rings that seal my favorite brand of cottage cheese are the same material. I like fluorescent stuff, so I've been collecting these ever since, as UV detectors. As you may conclude, I eat cottage cheese a lot; I have some with my breakfast at least twice weekly.

You may have heard of UV-detecting beads. They slowly change color in sunlight or when exposed to a UV lamp. There are several colors, but they all are clear once they've been away from a source of UV for a few minutes. The bonus of the fluorescent plastic is that it responds instantly.

Here I have a piece of the plastic hanging from a curtain rod in our sun porch. Some UV-sensitive beads are hanging with it, but their color change was rather subtle at the time this picture was taken. The blue tint of the plastic ring is evident…not overpowering, but evident.

This is a fresh ring. I noticed that, after six months in the sunny window, the ring that was there wasn't showing such bright fluorescence, and appeared more greenish. I replaced it with this new one and took it into my workshop to evaluate.

This photo under UV light shows the old ring on the right and a new one on the left. To the camera, they look very similar, but they look quite different by eye. This is at least partly because the camera sensor's color response is different from that of our eyes, and partly because the sensor can record UV, which is invisible to us. Also in the photo is a syringe I use for lubricating small parts, and also a reflection of the illuminating lamp, seen at the top of the photo. The desktop is dark brown Formica.

I decided to take a crude spectrum of these two pieces of plastic under UV illumination. I used this diffraction grating from Rainbow Symphony (the current price is $15 for a pack of 25). 

This grating has 500 lines/mm, which corresponds to 12,700 lines/inch. I have an old sheet of grating material from Edmund Scientific with 13,600 lines /inch, or 535 lines/mm, but it is harder to handle than these convenient slide mounts. Rainbow Symphony also sells gratings with 1,000 lines/mm, for those who want to photograph spectra at higher resolution.

This is the spectrum of the party light, tilted so that a sliver shows past the lampshade, at the left, with the main spectral lines noted. The filter isn't perfect, so visible lines of mercury come through. The very strong line pair centered on 406 nm gives the lamp its distinctive bluish-violet look, but it appears pure blue to the camera. There is also a faint orange-red line that I surmise is fluorescence from the filter material inside the lamp; mercury doesn't have a 620 nm line. Note how the 578 nm line pair appears yellow-green in the photo; to the eye it appears yellow-orange.

The UV wavelength that makes the plastic fluoresce is 365 nm. The camera can see it, as the photo shows. It is not visible to the eye, unless you have had a cataract operation; the natural lens of the eye is yellowish and filters it out. The strongest spectral line of mercury is 256 nm, but that won't pass through glass. A phosphor in the lamp filter fluoresces at 365 nm, increasing the efficiency of the lamp.

For reference, sunscreen and UV blocking sunglasses need to filter out all wavelengths shorter than 400 nm, or even 450 nm (mid-blue). In commercials, UVA refers to wavelengths near 365 nm, and UVC refers to 256 nm and nearby wavelengths. The middle range, called UVB, in the 320 nm range, doesn't have a convenient mercury spectral line to use for testing. Sunlight has a continuous spectrum of light that makes it through the atmosphere, from 180 nm in the deep UV (UVD) to 2,000 nm (mid-infrared).

This is a montage of the spectra of the two rings. I could have sharpened them by adding a slit above, but these spectra serve the purpose. The upper part shows the fresh plastic ring's spectrum. It fluoresces in the range from blue to green, with blue being brighter. The mix of blue and green makes the fluorescence of the ring look blue-white rather than deep blue.

The lower part shows the spectrum of the old, faded ring. There is less blue, but the green is unchanged. Thus, to the eye it appears greenish and dimmer when sitting in sunlight. That gives me a good reason to keep a bagful of these rings. About twice yearly I need to replace the "UV detector" in my porch window with a fresh ring.

These are useful to me, to remind me to wear sunglasses outside. I already have cataracts, but they aren't so bad that I need cataract surgery…yet. The more diligent I am to protect my eyes from UV, the longer I can do without it.

Too wrong to be wrong

 kw: book reviews, nonfiction, science, pseudoscience, sociology, humor

Imagine two utterly involatile items—tungsten ball bearings, say—orbiting one another in an absolute vacuum at a temperature very near absolute zero. The only force operating on them is their mutual gravitation. Based on the common meaning of the words, this system would be an example of perpetual motion. One could quibble that even in this microkelvin environment, an occasional tungsten atom volatilizes, such that over an extremely long time, occasional collisions between errant atoms and one or the other object would slow their orbital motion. I don't know how to calculate how long a time must elapse until the objects come to rest and, of course, settle into contact, nor how much longer before they evaporate away to a uniform tungsten gas. Certainly, our universe could not host a region in which this system is possible.

To would-be inventors, perpetual motion has a very different meaning: a system from which one can extract usable energy without adding energy.

This painting by Norman Rockwell, which graced the cover of the October 1920 issue of Popular Science, illustrates one of the many thousands of ingenious designs of perpetual motion machines. Just like all the others, a machine like this can be made with very low-friction components so that it will run for a very long time. But it will always slow down and eventually stop. If you try to extract some of its energy of rotation, it will come to a stop even sooner. Always, always.

The sociological phenomenon of "getting something for nothing" lies behind perpetual motion, and is the subject of Chapter 4 of  Pseudo Science: An Amusing History of Crackpot Ideas and Why We Love Them by Lydia Kang, MD and Nate Pedersen.

The authors state at the outset that the book is not comprehensive. Indeed, they shied away from overly politicized areas (e.g. Lamarckist and Lysenkoist theories of evolution) and the grossly evil ones (e.g. eugenic programs and vivisection, human and otherwise). Such things aside, they gathered 25 categories of pseudoscientific beliefs in four sections: "Pure Nonscience", such as flat-earthism, perpetual motion, and phrenology (bumps and lumps on the head); "Aliens! Ghosts! Bigfoot! Atlantis!", including UFOs (or UAPs these days), cryptozoology, and the "2012 Apocalypse"; "Wishful Thinking", or sundry ways to "predict" the future such as astrology or superstitions; and "Grifters, Nihilism and Denialism", where they lump in sundry conspiracy theories and dowsing.

Among the conspiracy theories they discuss, they do make a political foray, although I suppose they don't think of it that way: Climate Change Denial. What was once the Greenhouse Effect, from the early 1800's until the mid-1900's, became Global Warming before morphing another time or two so that now we hear of Climate Change, usually "catastrophic climate change". Here they toe the party line, the party of totalitarians. Sadly. Let's take a side trip into the facts as I know them:

• Joseph Fourier (he of the "series") in 1824 concluded that a "greenhouse trapping" effect by, primarily, water vapor caused the average temperature of the Earth to be warm enough to keep most of the planet's water in liquid phase.
• Svante Arrhenius in 1896 calculated the added effects of other gases, primarily carbon dioxide. He concluded that CO₂ could add a few degrees to the warming. The relevant sentence on p. 254 has Arrhenius stating that the added carbon dioxide "from coal combustion could result in global warming and possibly the extinction of the human race." This is utterly false. Arrhenius actually wrote,

"…we may hope to enjoy ages with more equable and better climates, especially as regards the colder regions of the earth, ages when the earth will bring forth much more abundant crops than at present, for the benefit of rapidly propagating mankind." 

He was from Sweden, and thought a bit of warmth would be beneficial. Just for the record, I consider that Canada, Siberia, and Patagonia will benefit, possibly to become the new breadbaskets of their respective continents, along with the Scandinavian countries. Further,

• As a teen I repeated Arrhenius's calculations. Later I majored in four sciences, with a "hobby" of computer coding (with which I paid my way until retirement). 
• In the regime of CO₂ concentration below about 1% (10,000 ppm), the absorption bands in mid- to longwave infrared "max out", or become saturated, before a concentration of 500 ppm is reached. In other words, with a present concentration of 425 ppm, nearly all the warming possible has already occurred. CO₂ in the atmosphere is increasing about 2.5 ppm per year, so the little bit of extra warming we can expect over the next 25-30 years is minor to negligible.
• Studies of fossils from times of high CO₂ and experiments with enclosed stands of trees where extra CO₂ is added to the air have shown that trees and other leafy plants grow faster and larger when CO₂ concentration is about 1,000 ppm, or 0.1%. This goes for rice also, contrary to some recent claims in overly politicized reporting.

"Global warming" and its various aliases was appropriated by the totalitarian Left in the US and much of the developed world as a cudgel to gain political control of the populace and the energy economy. They reason that only by creating an impoverished populace, including elimination of the middle class, can they achieve the power they crave. The deplorable condition of the Leftist-controlled major cities in the US, and their surfeit of impoverished minorities, portends the condition of all the world under Leftism.

Climate change has become a political tool, such that reasoned dialogue is no longer possible. OK, end of my soap box rant.

Much of the humor in the book is found in picture captions, such as, from the chapter Phrenology, an old illustration captioned, "An 1886 illustration of parents annoying children by stressing about their future careers," and in Cryptozoology, by an etching of a kraken dragging a ship into the sea, "This giant octopus would like a word about your sushi order." The text itself is straightforward, light-hearted in general, and a pleasure to read.

In the Personality Psychology chapter some ink is spent on MBTI, the Myers-Briggs Type Indicator. Many businesses use this to categorize (or label) employees. The category I fit is INTP, for Introverted-iNtuitive-Thinking-Perceiving. If the sixteen Types are taken as some fixed construct, being thusly labeled can lead to managerial abuse, which the authors dwell upon. However, at my company, at least, we learned the details of our assessments. Each Type Indication was based on our answers to a couple dozen questions. The final Indicator, such as the T applied to me, is a balance between opposing traits. Thus T and F, or Thinking and Feeling, go together. With up to 100 points to dole out, the T=7 in my score actually indicated 49T-42F, which means I am strong in both traits. As it happens, my career was built on my analytical skills, but I am also well known for my tendency to weep at weddings, and the way my son played the Toccata by Khachaturian at a recital also brought me to tears. The other three Indicators were also balances. I-E (Introversion-Extraversion), for example was stronger for I with a good dollop of E, and this is further influenced by the fact that I am somewhat bipolar: When I am "up" I am more sociable than otherwise, and "otherwise" tends to last longer. In this case, treating MBTI Types as prison cells is the pseudoscience. The authors rightly decry such practices.

In the chapter on the "2012 Mayan Apocalypse" it is a pity that they don't mention the excellent book, 2012: Science and Prophecy of the Ancient Maya, by Mark Van Stone, PhD, co-author of Reading the Maya Glyphs. In Dr. Van Stone's view, frequently stated, "December 22nd, 2012 will be akin to January 1 on our calendar."

The book is fun, interesting, and contains a bit of an Easter egg: The cover is printed in three colors of fluorescent ink, as these photos show.

This is a library book, and the dimmer section at lower left of the UV image is caused by library tape—which absorbs most UV—holding the catalog number to the spine.

============

My turn to give the copywriter a wrist-slap:

• On p. 105, the phrase "…more likely of the reeds' displacement" is missing a word and should read, "…more likely cause of the reeds' displacement."
• On p. 139, a picture of the Aztec Calendar Stone is labeled "The Maya Calendar." This is a very common error. The Mayan civilization fell before 900 AD. The Aztec civilization, featuring a different ethnic group, began about 1300 AD, four centuries later. The inscriptions of both cultures are distinctive and unique to each.
• On p. 155, pipes bursting due to freezing water are likened to a soda can bursting in the freezer. Sorry, but the latter eruption is due to CO₂ being driven out of the soda as it freezes. There is room in the can for water-to-ice expansion, but the CO₂ raises the pressure much higher.
• On p. 259, a more basic typo: a temperature rise of 2.5°F is equated to -16°C. This is a category error. As a temperature difference, 2.5°F equals nearly 1.4°C (of course, when the temperature is 2.5°F on a winter's day, that does equal -16°C).

Nature-nurture synthesis

 kw: book reviews, nonfiction, social science, genetics, dichotomies, syntheses

Many years ago I wrote a song for my parents, upon the occasion of their golden wedding anniversary. It was comprised of family stories based on the saying, "You came by that naturally." Among a cluster of verses, there are two refrains. The first is:

Is it Nature, is it Nurture? I don't know. Should I care?
In body, mind and feeling I'm their son.
Part of me is what they made me. Part of me I made myself.
What comes naturally, that's what I've been and done.

The second refrain is:

Is it Nature, is it Nurture? Why should anybody care?
We are dealt the cards, but our own hand we play.
When you put two lives together, almost everything you get,
You could say that you have come by naturally.

Of course,  the millennia-old debate between "naturists" and "nurturists" continues apace. One evocative song won't change that (though I hoped it might). I have always understood that everything, all our behavior, is an inextricable composite of "natural" (i.e. genetic) and "nurtural" (i.e. upbringing and environment), plus a strong component of our own free will.

Yes, I believe strongly in free will. That's where the second line of the second refrain originates. The "cards" are the natural and environmental raw materials from which we build a life. But make no mistake about it: we do the building. In everyone's life we find surprises, actions and decisions that nobody can attribute to a foreordained "cause."

In The Social Genome: The New Science of Nature and Nurture, by Dalton Conley, the Möbius strip is used as a metaphor for what seems to most of us a two-sided matter. If you've never played with a Möbius strip, try this. Cut a strip about an inch wide from the side or end of an ordinary sheet of paper. Tape or glue the ends together, but with a single half twist in the strip. Now you have an interesting geometrical item: a three-dimensional object that has one surface and one edge. You can verify this by drawing a line down the middle, all the way until the end of the line meets the beginning; also by coloring the edge with a felt tip marker, all the way until the end meets the beginning. Although at first glance this object seems to have two sides and two edges, they are actually one.

For a fun experiment, make a second Möbius strip and cut it down the center. I'll let you find out the result. If it evokes interesting thoughts, feel free to leave a comment about it.

I generated the image above using OpenArt's Qwen engine. I made dozens of images using six art generation tools before I found one I liked well enough to include here. This one is extra interesting because of the geometric shapes along the Möbius strip. Some of the shapes hint at chemistry, while others (especially the little heart in the blue circle) evoke relationships and other things.

Dr. Conley asks us to consider a family scenario. Looking first at genetics, let us consider a child's reaction to something new. Some children are shy, others bold, and some don't pay much attention after a first look. Can we say that this reaction is based purely in genetics? With a newborn who has hardly had time to observe his or her parents "in action," perhaps it is. Now consider the child after a few weeks, having observed the parents' reactions to various events. Has the baby's apparently instinctive reaction changed? If so, is it an entirely environmental influence? How much of either parent's reactions to new things is due to that person's generics, and how much to prior "environment", including upbringing? The chain goes back into prehistory! And that is just one characteristic among hundreds.

Looking again at free will, which Dr. Conley doesn't spend much time (or ink) on: Considering my son, I find several instances in which he took a direction that neither my wife nor I expected, based on family history. For example, before we married, my wife was an office worker, and I was a science major in college. I was hoping our son would be good at science. He is, but he has less interest in it than I expected; he became an English major. However, it is interesting that after we married, both my wife and I were educators. Our son's M.A. degree is in education, and he works as an educator.

Much of the book uses "genetics-environment" chains such as the one above to buttress an introduction to the "new science of nature and nurture" that the author is promoting, the science of Sociogenomics, which he and his colleagues are presently constructing. Much of the discussion centers on two key terms: GWAS and PGI:

• GWAS – Genome-Wide Association Study. A very broad-based study of specific characteristics of many people and their genomes. Many "traits" are found to be due to dozens or hundreds of genetic indications.
• PGI – PolyGenic Index. A "score" based on GWAS's for a specific trait, such as successful response to education. Few PGI's reach a level of great significance, so they are rather weak indicators.

Much is said regarding a person having a PGI that is "for" some trait or behavior. Later chapters dig into the influence of opportunity. For example, someone who "has a strong PGI for" educational attainment may never exhibit that trait if there is no opportunity to be educated: poverty, incarceration (maybe this one "learned" criminal behaviors better than others!), or living in a war-torn area. 

Looking back at that last sentence, I recall something my youngest brother said at our mother's funeral. Being the youngest, he was shown various techniques by his older brothers that became useful shortcuts in some of his classes. After telling a couple of stories he said, "Education is what happened when we weren't being schooled." Though he had done well in school, it is clear he didn't care much for it. He is the only one of us without a college degree but he led a successful life anyway (we are all in our seventies now).

It seems to me that Sociogenomics is in its very early days. It appears a bit ill-formed as yet. I wish Dr. Conley well in his endeavors. The "new science" could be promising. But it is unlikely to do much to end the N-N debate, at least among the ardent proponents of one or the other "ism".

==============

Errata etc.

• On p. 5 I find the first of several instances of "million" where "billion" is meant, when noting the three-plus billion nucleotides that make up the human genome.
• On p. 79, a typo: The surname "Woolf" is spelled "Wolf".
• On p. 82 we read, "…one's DNA blueprint is fixed at conception." Not entirely. We accumulate SNP's and other kinds of mutations in every cell of our body at the rate of about one per year. Frequently, a very early mutation results in different parts of our bodies having different genetics, often learning more toward one parent or the other from place to place. Visible evidence of such mosaicism in another species is the calico cat. Each visible body patch has different genetics.

I noted in passing a few other very minor typos and didn't bother to take note. All evidence of either a poorly educated copy editor, or the entire lack of one.

Intertwined biographies of man and fish

 kw: book reviews, nonfiction, science, oceanography, fishing, tuna, fish tagging, biographies

What a title to begin with: Kings of Their Own Ocean: Tuna, Obsession, and the Future of Our Seas, the new book by Karen Pinchin, chronicles the life of Al Anderson, the most prolific tagger of tunas and other fish, along with the natural history of bluefin tunas and the life of one particular fish that oceanographers named Amelia. In Mr. Anderson's website about the tagging of bluefin tuna, the fish in this photo is said to be Amelia, a fish that was first caught and tagged as a juvenile (the tag is the orange thingy hanging below the forward dorsal fin), then caught three more times; the records of her catch locations, and locations logged by a data logger upon her second "encounter" with oceanographers, robustly demonstrated that bluefin tuna range right across the Atlantic Ocean. This blew a big hole in a decades-old "two populations" convention that governed the catch quotas of fishing fleets. There is only one population of Atlantic bluefin tuna.

There! How's that for a spoiler? This lovely book winds together the lives of Al Anderson, his love of fishing, his eventually greater love of using tagging to gather scientific data about tunas, and the lives of the tunas themselves and Amelia in particular. Bluefin tunas went from being considered trash fish to become nearly the most valuable sea animal, on a dollars-per-pound basis. When big money is in play, old laws that permit or encourage overexploitation become deeply entrenched and unchangeable.

In the middle of the book the author notes in passing that bluefin tunas have chromatophores in their skin, and they can exhibit color and pattern changes similar to those of a squid. Note the skin pattern on Amelia in the photo. In most pictures showing a bluefin tuna, the blue-above-white color scheme is smooth, usually because the fish is dead. Amelia appears agitated, as a fish out of water ought to be! She lived another dozen or so years, and by her final capture and death in Portugal she weighed perhaps 600 pounds.

The book's title mentions obsession. Everything about fishing touches obsession: Al's obsessive love of fishing as a young man; his equally obsessive tagging program that began not that much later; the obsession of sushi-lovers for bluefin nigiri; the obsession for money that drives the entire bluefin fishery… The list goes on. Few people consider the tuna's obsession with staying alive.

Funny side note: We once met an elderly woman in South Dakota, who asked if I liked to fish. I don't, but I've done it whenever someone asks me along. I replied to her that I had fished a little, but I wasn't good at it, and that catching fish seemed to cost me more than going to the store to buy fish. She snorted, "Nobody fishes for economic reasons!" She loved to fish. I have my own obsessions, just not fishing!

In this case, a cluster of obsessions is driving the bluefin tuna to extinction. The future is bleak for this species.

They are all around us, essential to us

 kw: book reviews, nonfiction, science, gas, gases, vapor

This is a mercury barometer of a type one could buy in the late 1800's. In 1843, Evangelista Torricelli first filled a meter-long tube with mercury, held the end closed, and inverted it into a bowl of mercury. Some of the mercury ran out, but about 3/4 of a meter of the tube remained filled with mercury. This was the first demonstration that air has weight. It took some testing to verify that the upper part of the tube held a vacuum.

Torricelli showed that the pressure caused by the weight of about 76 cm of mercury in the tube equaled the pressure caused by the weight of the entire atmosphere, many miles in height. Under what a physicist calls "standard conditions" the height of the column of mercury is exactly 76 cm (29.92 in.), because that is part of the definition of standard conditions. The other parts of the definition are 25°C or 77°F, elevation at sea level (mean high tide), and zero humidity.

When a weather system moves through the area, the actual barometric pressure will differ, so that a barometer you may have in your home likely has a scale that runs from about 72.5 to 80 cm (~28.5 to 31.5 in.). It is really amazing that atmospheric pressure has more than a 10% range. Sometimes even more: in the eye of a hurricane it can be as low as 67 cm; the record is 66.9 cm, or 26.34 in.

The density of air under standard conditions is 1.2754 kg per cubic meter. Mercury is just over 10,000 times as dense as air, at 13,600 kg/m³. If air were incompressible and didn't thin out with altitude, the atmosphere would then be 10,660 times 0.76 meters, or 8.1 km thick (about 5 miles). But air does thin out with altitude, so a barometer can also be used as an altimeter: at an elevation of 8.1 km, air pressure does not suddenly drop to zero, but is 56.2 cm of mercury, or about 74% of sea level pressure.

Here is an interesting calculation: What is the volume of air that weighs one tonne (1,000 kg, or 2,205 lbs)? 1,000 ÷ 1.2754 = 784 m³. The dimensions of a travel bus such as a Greyhound bus are typically 13.5 m long, 2.6 m wide, and 2 m high; this amounts to 70.2 m³. An empty bus is carrying around about 1/12th of a tonne of air, which weighs some 90 kg or close to 200 lbs. A bus driver driving an empty bus has a hidden extra-large person along for the ride. By contrast, a suburban ranch house with an area of 1,600 sq ft, or 148 sq m, with 8-foot (2.44 m) ceilings, has a volume of 362 m³, so the air's weight is 0.46 tonnes, or 460 kg or a bit more than 1,000 lbs. It takes a pretty big house to contain a tonne of air. So air has weight, and moving air can move things, including sailboats and dandelion seeds, for example.

Thoughts such as these arose as I was reading It's a Gas: The Sublime & Elusive Elements That Expand Our World by Mark Miodownik. I had a slight qualm upon reading the title: most gases are not elements, at least in the chemical sense. The author is a scientist, so I figured he ought to know that. Perhaps "substances" or another semi-synonym for "elements" was deemed too clumsy by the editor. Alliteration before accuracy. But it put me on alert for other scientific solecisms, which I found (sad to say) and will mention later on.

It was soon apparent that the book has a cultural aim rather than scientific. There is a chapter on the "noble gases", helium, neon, argon, krypton, xenon and radon. That's the most scientifically oriented chapter in the book. These are the only gases that are actually chemical elements. All other gases that make it into our atmosphere (and all of them do) are molecular, starting with hydrogen, oxygen, fluorine and chlorine, which are diatomic molecules (H₂, O₂, F₂, and Cl₂) whenever they are not chemically combined with something else. The three most common triatomic molecules are ozone, carbon dioxide, and water vapor (O₃, CO₂, and H₂O). There are lots of gases!

This introduces the need for a definition. What is a vapor? In chemistry, a vapor is a gas that emanates from a substance that is a liquid at ordinary temperatures. At a high enough temperature, many liquids are entirely gaseous, and water becoming steam is the most familiar example. If it is too hot for water to exist as a liquid (at an ordinary pressure), it is too hot for us to live, being hotter than 100°C or 212°F. At lower temperatures, water vapor has a "vapor pressure" that is less than atmospheric pressure, so that at temperatures humans like, there is a little water vapor in the air, but only a small percentage. Another example is bromine. It is a liquid at room temperature, but its boiling point is 59°C or 138°F. Thus, it has a higher vapor pressure than water at any temperature below that.

Some gases are quite toxic, so-called "poison gases". Some, such as chlorine, were used in warfare—fortunately, more than 100 years ago, and not since. Others are mildly toxic but also reduce pain and have been used as anesthetics. In the past, ether vapor was a common anesthetic; it was used to knock me out for a tonsillectomy in 1952. Nitrous oxide is called "laughing gas" because it makes a person delirious, but doesn't make someone unconscious, while it makes them insensitive to pain. It is still in use. For most surgeries, other synthetic gases such as halothane work better than ether and are less toxic…but not totally nontoxic!

About 60 years ago I was a chemistry major. One thing we did, supervised, which probably isn't allowed these days, was to take a whiff of various vapors and gases. This probably saved my life. It was during the antiwar protests of "the sixties", and protests occurred regularly on campus. I would sometimes heckle the speakers at such rallies. One day when I opened my car I smelled the very distinctive odor of cyanide gas (HCN). I stopped breathing (without gasping!) long enough to open the door on the other side, and then I backed off and let the breeze de-gasify my car. I am thankful that "someone" was fool enough to try something tricky, rather than just wait for me with a gun!

Throughout the book there is an increasing emphasis on climate change and the role of CO₂. Interestingly, in one place, the author states that in the distant past, when the CO₂ content of the air was 5,000 ppm (half a percent), global temperature was about 10°C warmer than it is now. The current level is about 430 ppm. It is clear that he fully buys into the contention that rising CO₂ is an existential crisis.

Let's look at those figures, and add another. Pre-industrial times: 280 ppm, baseline temperature. Current: 430 ppm and 1°C warmer. Distant past, 5,000 ppm and 10°C warmer. The first two points define a straight line with a slope of 0.00667; the second and third points define a straight line with a slope of 0.00197. This is strongly nonlinear, so I tested this as a log-linear relationship. I find that it is quite a good fit. This allows me to interpolate that a level of 600 ppm is needed to add another °C, and 800 ppm would add one more degree. But that assumes that there were no other factors that contributed to the temperature in the distant past.

A different analysis, based on spectroscopy, one I first performed fifty years ago, indicates that at 400 ppm, the optical density of CO₂ is already about as high as it can get in the thermal infrared parts of the spectrum. In other words, it is already optically saturated, and the temperature is unlikely to rise even by one more degree. I conclude that we know too little about the situation when CO₂ content was 5,000 ppm.

Either way, that is not what I call an existential crisis.

In conclusion, the book is interesting and entertaining. It is really half memoir, half info-dump. A good combination! But I cannot pass by a few instances that reveal a bit of sloppy thinking:

• Discussing weather systems, on page 130, these sentences stood out, "Because of its lower density hot air expands, creating high-pressure regions. Cooler, low-pressure air moves to equalize the pressure and this air flow is what we call wind." This requires careful thinking. Warm, rising air causes lower pressure. Cold, falling air causes higher pressure. At the surface, the air moves from high to low. The only correct phrase is the last eight words.
• On pages 151 to 154, the discussion involves lighter-than-air ballooning using hydrogen and helium. The term "helium molecules" is found near the bottom of page 151. Helium does not form molecules. Under extreme conditions helium can barely be induced to react with fluorine, but this is not found in nature.
• Then on page 154, we read, "…hydrogen, a gas with an atomic weight of 1 atomic unit: it is 50 percent lighter than helium." An essential fact was left out. Helium is always monotonic, with an atomic weight of 4. Hydrogen in our atmosphere is diatomic, therefore, while the atoms have an atomic weight of 1, the diatomic molecules of hydrogen have an atomic weight of 2. That is why hydrogen is 50 percent lighter.
• On page 188, after a long dissertation on the search for "luminiferous aether", confusion suddenly arises when the author brings in Einstein. Aether was not "banished" by Einstein's 1905 special theory of relativity, it was Maxwell's Equations, published in 1865, that demonstrated that electricity and magnetism together (as electromagnetism) propagated each other through free space, and so no medium is needed for them to propagate through. A further statement about "how gravity works" is similarly anachronistic; gravity is dealt with in Einstein's general theory of relativity in 1915.
• A diagram on page 197 shows a portion of the solar spectrum, with Fraunhofer absorption lines, and certain ones prominently marked. The caption states that the lines are "associated with hydrogen." The C and F lines marked are indeed from hydrogen, but the D line pair is from sodium and the E line is from iron. Other lines also marked are also not from hydrogen.
• The diagram of the periodic table of the elements printed on page 205 is terrible! In particular, the shading in the18th period (inexplicably called VIIIA in the caption), the noble gases from helium to radon, is too dark to see the lettering. And this in a section in which the noble gases are the subject of discussion!
• Finally, on page 209, the work of Svante Arrhenius and his predecessor Eunice Foote is discussed, and simply bowdlerized. I'll leave out the detail. The thrust of the discussion is again inverted, leaving out the more important conclusions.

Might I say also, in discussions about the greenhouse effect caused by water, carbon dioxide, or other gases such as methane, I have never seen the point made that when the earth warms and radiates infrared into the atmosphere, these gases warm and re-radiate infrared in all directions. Thus, half of the re-radiating is downward and half is upward. This half-and-half phenomenon is important. Consider: CO₂ absorbs a few percent of the IR radiated by the warm soil. It warms up and sends some IR back to the soil, and an equal amount into space. Soil and atmosphere both get warmer, until the total radiation upward matches the total radiation downward. One must understand this point to accurately calculate the warming effect of a greenhouse gas. It is no simple equation, because the percent of absorption by the gas varies with wavelength. Search in Google Images for "carbon dioxide infrared spectrum" to see what I mean.

Spin – hard to avoid, hard to understand

 kw: book reviews, nonfiction, science, spin, rotation, angular momentum

Imagine a universe that consists of two identical objects. They can be single atoms such as helium (hydrogen prefers to exist as H₂ molecules, which complicates matters). Imagine further that these two atoms are some distance apart, initially with zero velocity with respect to each other. The only force acting on them is mutual gravitational attraction. Finally, consider that the same quantum mechanical laws apply to this universe as to our own.

Right away there is a puzzle. Quantum uncertainty, or Heisenberg's Uncertainty Principle, requires that the position and velocity of these atoms cannot be known with certainty. Therefore, as they begin to approach one another under the influence of gravity, it is not certain that they will collide. Some component of their velocities is bound to be off-center, and it is almost certain that they will miss. At the instant of closest approach, from the point of view of an imaginary observer exactly between them, they are moving at almost (but not exactly) equal speed, in opposite directions, at right angles to the direction of the line between them. Thus, they are in orbit about their common gravitational center. This universe now contains spin: a pair of neural helium atoms rotating about a common center.

To be sure, their orbits will be rather elongated, and at their greatest extent, they will be nearly stationary. But following their orbits, and doing the calculations, you would find that their combined angular momentum is constant throughout their orbits.

What is angular momentum? For two identical objects rotating about a common center, angular momentum is the product of the total mass times the velocity of each object relative to the common center, divided by the distance of each object from the center of rotation (the radius). For spinning solid objects such as tops or planets or Frisbees the definition (and calculations) are more complex, but similar in principle.

Now we can look at our universe as it is. The current cosmological theory states that after the initial expansion from a primordial singularity (the Big Bang), followed by "inflation", once the universe had expanded enough for its general temperature to allow atoms and molecules to form, all the universe was permeated by nearly uniform gas, about 75% hydrogen and 25% helium by weight. Quantum fluctuations led to broad volumes having a range of densities. I have usually read that the variation in density was around one part in 10,000. That was enough to cause the denser areas to begin to condense under mutual gravitational attraction. After billions of years the result is a sky full of stars, clusters, galaxies, galaxy clusters, superclusters, and most likely even larger structures that span large proportions of the entire universe.

AND EVERYTHING IS SPINNING (but not real Tasmanian devils)

In the book The Science of Spin: How Rotational Forces Affect Everything From Your Body to Jet Engines and the Weather, author Roland Ennos begins, not with the scenario presented above, but with an early airplane that was prone to crashing because of the angular momentum of its engine. The original Sopwith Camel was too powerful for its own good. How the WWI pilots and flight engineers solved this problem introduces the book's subject.

The book has twenty chapters, and thus twenty subjects. More than I thought there would be. The first five chapters (Part I) deal in detail with Earth. Rotation of the gas-and-dust cloud that condensed into the solar system allowed planets to form around the nascent star. The tides that follow the rotation of Earth under sun and moon, coupled with the temperature-evening-out effect of Earth spinning, made the planet habitable.

There is a thorough discussion of Coriolis phenomena, often called Coriolis forces, which result from initially linear motions across the surface of a spinning planet. In the absence of planetary rotation, air heated at the equator would rise, then move poleward, replaced by colder air from the pole that descends and moves equatorward along the surface. There would be a perpetual north wind in the northern hemisphere and a perpetual south wind in the southern hemisphere. Earth's rotation causes the upper-level air that begins to move northward to be deflected to the left, leading to east-to-west winds by about 30° N latitude, which then descends and is deflected as it is returning to the equator. This is the Hadley Cell. Two more bands form, one in temperate latitudes and another in the Arctic. A similar pattern is mirrored in the southern hemisphere. I note that the striped pattern on Jupiter reveals that this huge planet, more than ten times the diameter of Earth, but spinning more than twice as fast (in RPM terms), must experience much greater Coriolis effects, since there are apparently 30-32 zones of alternating higher-speed and lower-speed wind.

Eight chapters make up Part II, regarding the development of technology, and in particular the role played by rotating machinery. The history is fascinating, but rather overwhelming; there is so much of it. There is a little about conversions between rotatory motions and reciprocating motions; think of the rotating crankshaft in an internal combustion engine, coupled to the piston, which moves up-and-down or back-and-forth. Such conversions and similar themes are more the subject of Part III and its five chapters about the human body. To me, the culmination of the section is the discussion of throwing. 

The human shoulder joint is made for strong, accurate throwing, in contrast to the shoulder joints of all the other apes. This is why no chimpanzee or gorilla could become a baseball pitcher. Shoulder, elbow, wrist; each contributes to increasing the velocity of a throw, and each equally allows increased control for accurate throwing. By itself, the forearm is a sling pivoted on the elbow from the upper arm. The hand, pivoting on the wrist, is a secondary sling with an extra function: It allows a thrower or pitcher to spin the projectile, which stabilizes it in flight.

There is a great discussion of the mechanics of the trebuchet, or counterweigh catapult. This image is from the Ancient Technology website.

The throwing arm is driven by the heavy counterweight. The rope sling, with one end firmly attached and the other on a slip peg for release at the correct angle, adds great acceleration to the projectile. Take note of the angle of the counterweight in each diagram. The length of its attachment to the throwing arm determines when it "cocks", suddenly slowing the arm and facilitating release of the rope sling at the proper angle. This also facilitates accuracy.

I have made several small trebuchets for demonstration purposes. I helped our son and a friend of his build one for Science Olympiad on two occasions. The Olympiad had a "Storm the Castle" event for a few years. A catapult had to fit in a one meter cube when ready to throw. This is a view of several competing catapults awaiting the competition. Ours is at front and center.

The last two chapters, that make up Part IV, are a review of some historical point, and a backhanded complaint about the use of "spin" as a political term for biased reporting. Physically spinning may make you dizzy and confused. Being politically "spun" has a similar effect on one's understanding of current events.

It becomes clear that, while the mechanics of a single rotating object such as a planet or a top can be described with great exactness in an equation or two, the mechanics of a sports throw or the action of a trebuchet have no "closed form" mathematical treatment. Growing up in a physical body, we learn how certain aspects of spin work, in an intuitive and bodily way. We understand things "in our gut" far beyond what the math can discern. I am concerned for a generation of "digital natives" that have never gone outside to throw a ball around, or swing on a swing.

Amidst reading, I was sometimes irked at the length of explanations. But each time I had finished a portion, I realized I had learned something that a shorter treatment might have left unrealized. I am glad I read this book.

Errata: 

• On page 8: "Neptune … spins on its side." It is Uranus that is tilted almost parallel to it orbital plane.
• On page 38: Discussing the effect of Earth's spin on solar heating, "…alternately heated by the action of the sun during the day and allowed to cool when on the far side of the sun…" The last few words need to be either "on the far side of the Earth" or "on the far side away from the sun". The "far side" of the sun itself is just as hot as the near side!