My Flying People experiment

 kw: generated art, ai experiments, surveys, simulated intelligence, prompts, prompt adherence

Introduction

This is quite long so I include headings.

I remembered a science fiction story that I read decades ago, about a planet of creatures that looked a lot like humans, but had wings and flew about. Pondering a way to illustrate the central idea of the story, after some experimentation, I came up with this prompt:

On a planet with low gravity and dense air, many winged men and winged women are flying into and out of very tall buildings with doorways and landing platforms at every level

I was primarily interested in the great variety of imaging Models offered by Leonardo AI, and I had thousands of credits available. I surveyed nearly all the possibilities in Classic State, which yielded 184 images, all based on a particular Seed; more on that anon. I also used the prompt to produce much smaller suites of images with Dall-E3, DesignStudio, Gemini, and ImageFX. To jump ahead to a useful conclusion, I found that Dall-E3 produced images closest to the meaning of the prompt; in the lingo of the field, it has the greatest Prompt Adherence. Here are two examples, the best of the 24 images I gathered from Dall-E3:

I am showing two images because the first has the best people and the second has better buildings. When prompting an art generating program, it takes persistence and cleverness to get good adherence to a complex prompt. BTW, did you notice the figure with wings on backward?

Models and Styles

Leonardo AI (henceforth Leo) has thirteen Models or Presets and each has a number of Styles, as many as 23. This is a list of the 13, with the number of Styles each includes, and the cost in credits per four images, the usual number. The free program assigns 150 credits daily. It is easy to use them up pretty fast! The basic monthly subscription assigns 8,500 credits per month for $12. These pile up fast unless you are very active. I wish there were an in-between subscription level such as 3,000 credits for $5.

The total number of Styles is 61, and the number of Model+Style combinations is 194. I did not quite use them all. Several Styles are named Monochrome or include B&W in their name and those don't interest me.

Seeds

Leo also has the option of using a fixed Seed. Leo's help text says that this Seed is used to generate the "noise" that the reverse-diffusion process starts with to produce an image. That is not all there is to it, because the Seed value also influences the Transformer (the routine that figures out object identity and placement, which defines the goal toward which the diffusion algorithm operates). Seeds in Leo (also DreamStudio) have six digits.

When I set a fixed Seed, I tend to pick Seed values that are a multiple of 999,999/7 or 999,999/13, all of which have six digits except 999,999/13, which is 76923. After a period of noodling around, I found the region around 428571 (3*999,999/7) most interesting and settled on 428575. All the images shown here were produced using this Seed.

Selection 1: Leonardo Lightning Style Gallery

No matter how I may group the images, it would be tedious for the reader to wade through a discourse on 184 images. Thus I picked certain themes. I chose primarily certain Styles across all the Models, but I will start by showing the gamut of Styles for the Model called Leonardo Lightning (or LLightning), which runs faster than the others and costs the least—two credits per Medium-size image (1280x720), while for most Models the cost is 3 or 4, and it goes up to 12, and even higher where larger images are available in certain Models.

Forthwith, the gamut of LLightning images, screen-captured three across from File Explorer, so the file names can be seen:

The last image above is from the next set, from the Model Phoenix 0.9.

LLightning is unique among Leo's Models; 16 of the 21 Styles shown here produced things with wings, but only 7 are winged people. The third Style, Cinematic, has what appear to be human-sized bats, but they may be humans with bat wings. It is hard to tell which, even on the full size image. Two others show beetle-like flyers, two have birds, and the flyers in the other 4 images are unidentifiable. Finally, the images from None and Unprocessed are apparently identical, which I find logical: both claim to be doing nothing "extra" to the Model. This is also seen for the Model Cinematic Kino, the only other Model that offers both None and Unprocessed.

Compared to the other Models, this mix in LLightning is interesting. Four Models (the two Phoenix versions and the two Flux versions) adhere to the "winged" part of the prompt 100%, although only the two Phoenix versions have winged persons in all images, while the two Flux versions have more birds and fewer people. On the other hand, two Models (Graphic Design and Stock Photography) never produced wings on anything. Most of the Models yielded low percentages of winged persons. Anime is unique in a different way. Half of its Styles produced images with winged humans and two Styles have airborne humans without wings (one hopes they are floating, not falling). Only two Anime Styles had no wings at all.

Selection 2: Model Galleries for nine Styles

Style 1 = None (10 uses)

Now I will focus on particular Styles as developed in different Models. The Styles to be presented are those having larger numbers of Models that use them, in descending order by usage numbers. The first is None, meaning no Style was applied. This (non-)Style is available for the largest number of Models (10), with a modification to be mentioned below. I used a search to isolate each set of images, and a quirk of the search function is that the images are presented in reverse order.

In the next-to-last row of images, the first two appear identical. Upon very close inspection I find a few tiny differences. In the row above that, the second and third image are, so far as I can tell, identical. This shows that behind the scenes Portrait Perfect and Cinematic Kino use the same engine, as do Graphic Design and Illustrative Albedo. So in this case the 10 Models produce 8 unique images (discounting a few nearly invisible differences in one case). These images show what each Model produces when it is not constrained by a Style.

Style 2 = Dynamic (8 uses)

Dynamic is the default Style for the 8 Models that use it.

For the Dynamic Style, the image I like best is for Phoenix 0.9. It is the best match to the image I had in mind after reading the story, so long ago. Comparing all these images with the prior set, I find that for Flux Schnell the Dynamic Style produces the same image as None. Similarly for Flux Dev, Phoenix 1.0 and Phoenix 0.9. For the other Models, these Styles produce significantly different results. Three of the Models—Illustrative Albedo, Cinematic Kino and Lifelike Vision—have what I call "winged structures", although one of them (for Cinematic Kino) looks like an immense beetle.

At this point note that "doors at all levels with landing platforms" is seldom found, and that is primarily in Phoenix 0.9.

Style 3 = Portrait (8 uses)

As we'll see later for the Fashion Style, Portrait often emphasizes a central figure, although in the case of Illustrative Albedo, that figure is a flying structure, looking like a giant crab with 6 wings. The image from Lifelike Vision has a figure with wings that are more like hang glider wings, rather than bird wings. But, wings they are.

Style 4 = Stock Photo (7 uses)

Stock Photo is the only Style used by the Stock Photo Model. Its image is almost identical to the one produced by Cinematic Kino, but not entirely (one must look hard to find the differences). The other 5 Models all yielded winged things with this Style, but only the image for Phoenix 0.9 has winged people.

Style 5 = Ray Traced (7 uses)

Now we can start to see that certain Models, such as the two Phoenix Models and the two Flux Models, have the primary influence. In other cases, the Style seems to be "stronger" than the Model. Other than having a brighter and more colorful appearance, Ray Traced is similar to Stock Photo. For this Style, only the Phoenix Models produced flying people.

Style 6 = Illustration (7 uses plus "Anime Illustration")

It is more clear with these, compared to the prior sets, that the Style is paramount for LLightning, Illustrative Albedo, and Lifelike Vision. Here, Anime Illustration Style in the Anime Model joined the Phoenix Models in producing flying people.

Style 7 = Fashion (7 uses)

Here is a Style that produces winged people, almost 100%! Lifelike Vision's person has a winglike, flowing robe. Perhaps the presence of about 8 wings on the person in the Cinematic Kino image makes up for that… As one might expect from the name, a "fashion model" is front and center.

Style 8 = Creative (uses = 7)

Following trends we've seen above, some of these differ from other Styles for a particular Model, while a couple of them are more similar. Only Flux Dev and the Phoenix Models produced flying people. The flying things in the LLightning image seem to be huge insects though one of them has feathered bird wings. I don't know why a scattering of these images feature hot air balloons.

Style 9 = 3D Render (7 uses, with two added sizes)

As mentioned earlier, most of these images were generated for the Medium 16:9 size, which is 1280x720 for most Models, but is 1184x672 for the Phoenix Models and the Lux Models. I did a side experiment to show the effect of changing image size with Phoenix 0.9. You can see in the file names for "LPhoenix09" the numbers 01a, 01b, and 01c. The image sizes are 1184x672, 1376x768, and 1472x832. When I want to use any Phoenix image for a 16:9 wallpaper, these sizes are a little off. Leonardo can upscale an image so it is larger than 1920x1080 (full HD), but then trimming is needed to get an exact ratio. Changing the size causes changes in the overall image, though the three images are similar.

For this Style, the Phoenix Models produced flying people, but the others differed: LLightning and Flux Dev made flying beetles, Flux Schnell made birds, while Illustrative Albedo and Lifelike Vision produced lots of balloons but nothing with wings.

Wrap-Up

The Leonardo AI Models definitely have minds of their own. Only images produced by Phoenix 0.9 had both elements, flying people and towering buildings with landing pads at upper levels. Few other Models had the buildings as I had asked. Generally, the images are somewhat inspired by the prompt, sometimes rather distantly. It would take a lot more investigation, letting the Seed be randomly produced, to see whether any particular Model+Style is capable of better compliance.

I use art generating software as a "commissioned artist". A few of the Models in Leonardo, the more costly ones, are reasonably compliant. Programs other than Leonardo vary in their Prompt Adherence, and Dall-E3 is probably the best. The rest of Leo's Models, in most of their Styles, are fun to experiment with, but are unlikely to yield results that well match anything but the simplest queries.

I did not test a rather new way of using Leonardo AI, Flow State. It has a different way of doing things. Neither did I turn on "AI Enhancement" for my prompt in those Models that offer it. What we have here is complex enough already.

The folders of images I produced are a useful Gazetteer of possibilities that I can use in the future to select an image generation routine.

Insects – making friends of foes

 kw: book reviews, nonfiction, insects, entomology, surveys

Books about insects usually focus either on their beauty and diversity, or on problems and pests. Metamorphosis: How Insects are Changing Our World, by Erica McAlister with Adiran Washbourne, introduces us to the mysteries of metamorphosis before focusing on the usefulness of certain insects. (Image produced using Dall-E3, after lengthy negotiations and creative prompting. The text was added afterward.)

More than 80% of insect species undergo complete metamorphosis, in which the life stages are Egg, Larva, Pupa, and Adult. The rest have incomplete metamorphosis, in which instead of a larva (such as a caterpillar or grub or maggot), there is usually a nymph that looks more and more like the adult as it grows, and there is no pupa stage. A major chapter of the book outlines the history of discovery of the stages of metamorphosis. Note that many creatures other than insects have metamorphosis, sometimes with many more than four stages.

Do you get itchy just thinking about fleas? So do I. The way they store energy to be suddenly released in an astounding jump was studied, which revealed resilin, the most elastic protein known. It can release very nearly 100% of the stored energy, very fast. It required numerous advances in photographic technology to develop camera systems that could take images fast enough to record an event that takes just one or two thousandths of a second, so the takeoff mechanism could be studied properly. Scientists also needed to learn how to induce a flea to jump on demand, in the presence of large, noisy pieces of equipment and large, looming humans! Synthetic resilin and resilin-like polypeptides are revolutionizing the elastomer industry.

Where would the genetics revolution be without the lowly fruit fly? The species used for decades now to winkle out the laws of inheritance, Drosophila melanogaster, actually a vinegar fly, has four gigantic chromosomes, rather than the dozens of more tightly-wrapped ones found in other critters. These flies also have the virtue of short lives and tiny size, so you can keep hundreds in a small space and feed them bananas, and do multi-generation studies in months rather than decades.

I'll skip forward to the last chapter, about cockroaches. (Ugh! you say...me, too.) They have a distributed nervous system that (this is my take) seems to act like a meta-brain, which makes a roach quite a bit smarter than other insects of comparable size. They also react faster; in my experience (when I lived in Houston), while I can usually swat a fly, I had no better than 50% success swatting roaches.

And what might we say of blowfly maggots (bigger Ugh from most), which help forensic detectives estimate how long ago a murder victim died; or soldier flies, which don't carry disease and whose maggots are super-nutritious and very fast-growing, so that they are called "ultimate upcyclers" as they turn food waste into food (I don't know about you, but I'd cook them first); or metallic colors on blue butterflies and green beetles (and many others) that have led to the development of color-shifting coatings for autos and dazzling paints that won't fade; or the unique hydrophobic-hydrophilic array on Namibian beetles that can harvest water from misty air?

The usefulness of insects has not been surveyed before in the way I find here. This book is way beyond just "fascinating"!

If it is artificial, is it intelligence?

 kw: book reviews, nonfiction, computer science, artificial intelligence, simulated intelligence, surveys

Before "hacker" meant "computer-using criminal", it meant "enthusiast". Many early hackers spent their time obsessively doing one of two things: either writing a new operating system, or trying to write software to do "human stuff". I have been hearing about "AI", "artificial intelligence" since the term was coined by Claude Shannon when I was nine years old. Two years later the third book in the Danny Dunn series was Danny Dunn and the Homework Machine (by Abrashkin and Williams). It featured a desk-sized computer with a novel design, created by a family friend, Professor Bullfinch. A decade later (1968) I had the chance to learn FORTRAN, which kicked off a lifelong hobby-turned-profession. The computer I learned on was the first desk-sized "minicomputer", the IBM 1130.

ENIAC and other early "elephants" were called "electronic brains" almost from the beginning. I learned how CPU's (central processing units) worked, and even though the operation of biological brains was not so well known yet, it was clear to me that computers worked in an utterly different way.

Fast-forward a few decades. Some 20 years ago a "last page" article in Scientific American described the newest supercomputer, claiming that it was equivalent to a human brain, in memory size, component count, and computing speed. Where it did not match the brain was the amount of power it needed: three million watts. Our brains use about 20 watts. It soon became evident that the metric of brain complexity is not the number of neurons, but the number of synapses, plus other connections between the neurons and the glia and other "support cells". In this, that supercomputer was woefully lacking. This is still true.

Tell me, does this illustration show one being or two?

My generation and all those following have been influenced by I, Robot, and by Forbidden Planet, and by other popular depictions of brainy machines. We think of a "robot" as a mechanical man, a humanoid mechanism that is self-contained.

In order to behave and respond the way one of the robots in I, Robot does, a humanoid mechanism would need an intimate connection with a room full of equipment like the supercomputer in the background of the image (that part of the image is real). When the Watson supercomputer played Jeopardy (and won) a few years ago, what the audience didn't see was the roomful of equipment offstage. And that was just what was running the trained "model" and its databases and the voice interface. The equipment used for training Watson was much larger, and kept a couple of hundred computer scientists, linguists, and other experts occupied for many months.

Assuming Moore's Law continues to double circuit complexity (per cubic cm) each two years, it will take sixteen doublings, or 32 years, to get the supercomputer shown into a unit that fits inside a robot of the size shown. And power requirements will have to drop from millions of watts to 100 watts or less. And this is still not a machine that has the brain power of a human. We don't know what that would take.

All this is to introduce a fascinating book, The Mind's Mirror: Risk and Reward in the Age of AI, by Daniela Rus and Gregory Mone. While Professor Rus is a strong proponent of AI and of its further development, she is more clear-headed than the authors of most books on the subject. In particular, she sees more clearly than most the risks, the dangers, of faddish over-promotion and of rushing blindly into an "AI Future".

At the outset, in Chapter 1, "Speed", she clearly emphasizes that products such as ChatGPT, DALL-E, and Gemini are tools, and particularly that their "expertise" is confined to the material that was used to train them. She writes that it might have been possible to get one of the LLM's (large language models) to write a chapter of the book, but it "would not really represent my ideas. It would be a carefully selected string of text modeled on trillions of words spread across the web. My goal is to share my knowledge, expertise, passion, and fears with regard to AI, not the global average of all such ideas. And if I want to do that, I cannot rely on an AI chat assistant." (p. 11) In a number of places she calls AI software "intelligent tools."

She continues the theme, writing of knowledge, insight, and creativity (Chapters 2 – 4), saying at one point, "They are masters of cliché." (p. 60) Critical analysis skills that we used to learn were based on following the progression from Data to Information to Knowledge, and then to Insight and Wisdom (does any school still teach this?) All of these together add up to comprehension. Does anyone have the slightest idea how to bring about Artificial Comprehension?

None of the software tools has shown the slightest ability to step outside the bounds of their training data. If ChatGPT "hallucinates", it is not rendering new knowledge, but remixing biased or deceptive content from its poorly curated training set, perhaps with a dollop of truthful "old news" in the mix. This illustration of a LinkedIn post I wrote last year shows the point.

The colors are significant:

• Green = correct or true
• Lighter orange = incomplete or outdated
• Darker orange and red = false to malicious, even evil
• Blue = AI training data, partly "good", partly "poor", partly "evil"—we hope not too evil

The three lavender blobs at right are varieties of human experience, including someone creating new "good stuff", poking out to the right and increasing the store of published knowledge. I kept those blobs far from the training data on purpose. Training is typically done with "old hat" material.

This book has a rare admission that "it's essential to remember that the nature and function of AI parameters and human synapses are vastly different." (p. 106) We don't know all that well the amount of processing going on within a neuron, nor even if a synapse is more than just a signal-passing "gate" or is something more capable. 

And though the matter of embodiment is touched upon, I was disappointed that there wasn't more on this. Perhaps you've heard that the human brain has "100 billion neurons". The actual number is 85-90 billion, and 80% of them are in the cerebellum, the "little brain" at the back, above the brain stem. We have a little inkling that the sorts of processing that cerebellar neurons perform are different from those in the cerebral neurons (the famous "gray matter"). Clearly, when 80% of the neurons make up only 10% of the brain's total volume, these neurons are smaller. The cerebellum "runs the body", and handles the traffic between the body and the cerebral cortex, the "upper brain", where thinking (most likely) occurs. Embodiment is clearly extremely important for a brain to function properly. It's being glossed over by most workers in AI.

A special chapter between 11 and 12 is "A Business Interlude: The AI Implementation Playbook". An entrepreneur or business leader who wants either to initiate a venture that strongly relies on these tools, or who wants to add them to the company bag of tricks would do well to extract these 19 pages from the book and dig into them. They include the key steps to take and the crucial questions to ask (including "Will AI be cost-effective compared to what I am doing now?"). A key component of any team tasked with making or transitioning a business to use AI is "bilinguals", people who are well versed in the business and also in computer science and AI in particular. This is analogous to a key period in my career (not with AI, though): Because I had studied all the sciences in college, and had a few degrees, and I also was a highly competent coder, I was a valued "bilingual", getting scientific software to work well for the scientists at the research facility where I worked. Bottom line: You need the right people to make appropriate use of AI tools in your company.

The book includes a major section on risks and the defenses we need. Whether some future AI system will "take over" or subjugate us is a far-off threat. It is not to be ignored, but the front-burner issues are what humans will do with AI tools that we need to be wary of. Something my mother said comes back to me. I was about to go into a new area of the desert for a solo hike. She said she was worried for my safety. I said, "Oh, I know how to avoid rattlesnakes." She replied, "I am worried about rattle-people!"

Let's keep that in mind. In my experience, rattle-people are a big risk whenever any new tool is created. What's one of the biggest uses of generative art-AI? Coupling it with Photoshop to produce deep fake pictures. Deep fake movies are a bit more difficult and costly just now, but just wait…and not very long! Soon, it will take a powerful AI tool to detect deep fake pix and vids, and how will we know that the AI detective tool is reliable and truthful?

A proverb from my coding days, "If we built houses the way most software is written, the next woodpecker to come along could destroy civilization." Most of us old-timers know a dozen ways to hack into a system, but the easiest is "social engineering," finding someone to trick into revealing login credentials or other information to help the hacker get into the system. Now social engineers are using AI tools to help them write convincing scripts to use to fool people, whether through scam phone calls, phishing emails or smishing SMS (or WhatsApp or Line or FB, etc.) messages.

[You can take this to the voting booth: Effective right now, any TV or radio political ad, particularly the attack ads, will have AI-generated content. If you want to know a candidate, go to the candidate's web site and look for actual policy statements (NOT promises!).]

A final matter I wish Professor Rus had included: Human decision making requires emotion. Persons who have suffered the kind of brain damage that "disconnects" their emotions become unable to make a decision. Somehow, we have to like something in order to choose it. Where "liking" comes from, we haven't a clue. But it is essential!

There is much more I could go into, but this is enough, I hope, to whet your appetite to get the book and read it.

A final word, that I didn't want to bring into the earlier discussions. I don't like the term Artificial Intelligence, nor AI. I much prefer Simulated Intelligence, abbreviated SI. It is unfortunate that, in the world of science, SI refers to System Internationale, the system of units such as meter, kilogram and second, used to define quantities in mathematical physics. Perhaps someone who reads this can come up with another moniker that makes it clear that machine intelligence isn't really intelligent yet.

Exoplanets survey

 kw: book reviews, nonfiction, astronomy, astrophysics, exoplanets, surveys

Imagine what planetary astronomy would be like if there were frequently two or even three planets visible in the sky that appeared similar in size to the Moon as seen from Earth. And I do mean "frequently." The planet currently known as Trappist-1e, the fourth planet around the small star Trappist-1, has a six-day year. From a dark-sky location, on the side away from its sun, the next planet outward (-1f) would reach superior conjunction about every dozen days, having a visible size of 34 arc-minutes; we see the Moon as about 33 arc-minutes across. The apparent size of -1g, another step outward, ranges up to 19.5 arc-minutes, nearly 2/3 of a "moon unit". From locations near the terminator (the star-rise or star-set line), the next planet inward, -1d, approaches 32 arc-minutes at inferior conjunction, as a crescent, just as Venus at its brightest is seen as a crescent because it is nearly between the Sun and the Earth. Even when the other six planets are at opposition (on the other side of the star), they always appear larger than any of the planets in our solar system ever do: even Venus at near-conjunction is too small to show a visible disk, except to a few folks with test pilot vision. All the Trappist-1 planets are always seen as disks.

From planet -1e, however (and any of the others, from -1b through -1h) there probably is no star-rise or star-set. So far as we can tell, they are all in tidal lock with Trappist-1, the way the Moon is with the Earth. It is also unlikely that three big neighboring planets can be seen in the sky at the same time because the orbital periods are all in resonance, which keeps them from lining up in the sky simultaneously.

If you were on the brighter side of the planet, the star would appear much larger than the Sun, about seven times its size. But its surface brightness is lower, by far, than the Sun's. It would still be risky to look right at it. Imagine looking at a ball of near-molten tungsten at a temperature of about 2,560K (~2,290°C or ~4,150°F), just slightly cooler than the filament in an incandescent light bulb. Although astronomers call this star a "red dwarf", one of the reddest known, visibly it appears orange-white. It would be dazzling, even though our Sun is 1,800 times as bright.

All of these facts are consequences of the small size of the Trappist-1 stellar system. The outermost known planet, Trappist-1h, revolves at a distance of only 8.8 million km from the star (from Earth to the Sun is 149 million km). The star's faintness, however, means that the habitable zone is between 3 million and 5 million km. Both Trappist-1d and -1e are within this zone, and maybe -1f and -1g, while -1h is "out in the cold" and always frozen (like Mars) and -1b is rather like Mercury and subject to searing heat (from 125°C to 230°C, or 255°F to 505°F).

All of this has been learned from viewing the Trappist-1 stellar system using several telescopes (at least 3 of them in space) and spectroscopes. The procedures and the kinds of data needed to discover and characterize exoplanets are described in a very understandable way by Joshua Winn in The Little Book of Exoplanets. Considering that there are more than 5,500 known exoplanets presently known, Dr. Winn makes a good point that we need to set aside the term "exoplanet" and just call them "planets." Our stellar system, which includes eight planets, is just one of more than 4,100. More planets, and more systems having two or more confirmed planets, are being discovered daily.

All of the earliest discoveries were made using the Doppler method, which measures how much the star is moved back-and-forth by a planet. Naturally, the easiest sort of planet to discover, by nearly any means, is one that is large (that is, massive) and close to its star. Big Doppler shifts are easier to discern, and shorter orbits take less time to confirm (days or months rather than years or decades). For one method, though, direct observation using a coronagraph, big planets that are far from the star are easiest to see. Finding smaller, less massive planets, in years-to-decades-long orbits is between difficult and (so far) impossible. None of our current methods could reliably discover Mercury, Venus, Earth, or Mars, and also Uranus and Neptune. Saturn and Jupiter are on the "possible edge". So it is no surprise that systems similar to our own have not yet been observed. Proclamations that our system represents something very rare are premature. We don't yet have a way to know!

The most prolific method so far is the transit method. When the system is lined up just right, one or more of its planets will periodically cross in front of the star, which dims its light a tiny bit. This illustration compares observations of a transiting planet made from Earth's surface with observations made using the Kepler Space Telescope. The atmosphere, even using adaptive optics, is a big handicap to precise observation.

During the useful lifetime of the Kepler telescope I used Zooniverse to make some of the measurements in a Citizen Science project called Planet Hunters. I don't think I made any new discoveries, but I think my work helped others confirm at least a few of them; the stats show that I made 6,866 classifications. Most of them were "no planet".

This image, Plate 16 in the book, shows the Starshade concept: A space telescope will have a co-orbiting daisy-shaped shade that blocks the light of one particular star with sufficient efficiency that direct observations of planets near the star can be made. The shape of the bladed disk is optimized to "spread around" diffraction effects so that a star's light can be reduced by a factor of several million or even a billion, while the nearby space, within a fraction of an arc-second, is unimpaired.

Such a system could see Earth, probably Venus, and maybe Mercury. "Co-orbiting" in this case means the telescope and the shade are about 30,000 km apart in a very high orbit! They would need to be supplied with large amounts of fuel to allow for frequent re-positioning and re-aiming. Perhaps by the time these are commissioned, paid for, built and orbited, we'll finally have a successor to the Space Shuttle that can reach high orbits so they can be refueled. Running out of fuel is the bugaboo of space observatories.

This is more than just curiosity. Every space observatory since Hubble has had as part of its ambit, "Help find habitable planets and planets with life, even intelligent, communicating life". Whether or not Earth is utterly unique in the Galaxy (if not the whole universe) is the biggest question science can address. (My note: It's curious that the budget of NASA is in the range of 1/200th of the Federal budget. The yearly spend of SpaceX and all the other private rocket companies that have sprung up in the past decade or so totals between 1/10 and 1/5 of NASA's budget. To get a "supershuttle" into operation and to genuinely support "big space astronomy", these numbers have to increase by a factor of ten or more.)

I am quite enamored of exoplanetary science. This "little book" is packed with great info and stories about its current condition.

The first empire

 kw: book reviews, nonfiction, archaeology, antiquities, paleography, surveys, biblical connections

It takes a while to read through a 450-page book, even one as interesting and well written as Assyria: The Rise and Fall of the World's First Empire by Eckart Frahm. While Assyria may not be a hot topic to most people, it is familiar to anyone who reads the Old Testament, where Assyria and the Assyrians are mentioned 141 times, and all the Assyrian kings that could be called emperors are named: Tiglath-Pileser, Shalmaneser, Sargon, Sennacherib, Ashurbanipal (called Asnapper in Hebrew), and Esarhaddon. These six "great kings", who collectively reigned from 744 BCE to 631 BCE encompass nearly the entire time span that Assyria can be reasonably called an empire. By 631 the empire had begun to fall apart, by about 620 it was moribund, and by 609 it was no more.

When I saw the designation, "first empire" I thought, "Wasn't Akkadia an empire before Assyria? And could the Sumerians, during their expansion era, be considered an empire?" The author discusses just these things in Chapter 5 – The Great Expansion, which begins the section denoted Empire. He describes a change in style, not just size, that differentiates Assyrian hegemony from the earlier expansionist kingdoms. It is one thing to subdue a number of external polities for the sake of tribute, and quite another to rule them administratively. Having chosen to draw the line there, the author can fairly claim Assyria as the first true empire. In a later chapter he points out that Babylonian, Persian and later empires, right up to modern times, learned administrative and political lessons from the Assyrian example.

I was quite taken by a somewhat side point, that the Assyrian language was, in early and middle times, written in cuneiform on tablets, such as this one from about 1900 BCE. It is housed at The Met.

Clay tablets are durable, so there are tens of thousands of them, in Sumerian, Akkadian, Babylonian, and both early and late Assyrian languages. This is a letter about buying textiles.

"Cuneiform" means "wedge writing". The stylus has a triangular profile, and a scribe could write just by tapping. It was faster than you might expect (my brother and I tried to learn to do it, but it takes tons of practice to tap with both speed and accuracy).

Assyrian in particular was to be read from left to right, in lines down the page, like most modern writing systems. The earliest Sumerian tablets, however, were in columns from top to bottom and the first column was on the right, like classical Chinese.

By 2200 BCE, when this tablet was written, Sumerian was also being written from left to right. The content of this tablet, the oldest one in the collection of Cambridge University, is about commercial transactions. Note the difference in scribal style. In particular, this tablet has deliberately inscribed lines between rows of text, while the Assyrian tablet has the glyphs "hanging" from horizontal top lines produced as each glyph is written, much like Sanskrit.

The huge number of tablets that have been found throughout Mesopotamia enable a rich view into the people who wrote them. Monumental inscriptions, also in cuneiform, concern kingly affairs and stories of conquests in war. However, many tablets are from merchants writing to merchants and other people writing of mundane matters.

A note on dates. In daily life I am like most people, using "BC" and "AD" (which mean "Before Christ" and "Anno Domine", meaning "After the Lord") to refer to historical dates. However, it is well known that Jesus was not born in the year just before 1 AD, which we would call 1 BC; there is no Year Zero. The "AD" era was determined when less was known about the death of Herod the Great, the king who attempted to have the baby Jesus killed shortly before his own death (from a few months to a year, most probably). Based on his interview with the Magi, Herod ordered babies in Bethlehem to be killed "up to age two", because of the time the "star of Bethlehem" first appeared. In Matthew, when the Magi found Joseph and Mary and Jesus, they were in a house, while in Luke, when the shepherds found the family, they were still in the stable where Jesus was born. It is implied, but not clearly stated, that the star appeared when Jesus was born. If so, he was two years old when the Magi visited (so Crèches are anachronistic). The gifts of the Magi funded the flight of Joseph and his family to Egypt until Herod died. Even now it is not certain which year Herod died. There was an eclipse at that time, but it may have been either in 1 BC or 4 BC. So Jesus was born some time between 2 BC and 7 BC. By the way, we know the crucifixion was in April of 32 AD, and the story in Luke implies that He was born in the springtime, so the age that Jesus attained was between 33 and 38. The common Christian meme that He died at the age of 33½ is certainly wrong by at least half a year, and possibly by 4½ years. Now to the point. In Assyria the author uses the archaeological convention of "CE" instead of "AD" and "BCE" rather than "BC", where "CE" refers to "Christian Era". That removes the theological element from archaeological calculations. Herein, I follow the same convention.

Assyrian culture developed over a millennium and a half, centered initially on the city of Ashur, which was also the name of their god. The town lay on the Tigris River, now in northern Iraq, east of northern Syria. The first "king" of Ashur, more of a mayor I would say, was in the 23d Century BCE, or 2250 plus or minus 50 years. About 2000 BCE the king of Ashur began expanding his realm, and incorporated Nineveh, which had already been an occupied place for 4,000 years. This began the Old Assyrian Period. The author places the beginning of a transition period in about 1735 BCE, and its end about 1400 BCE, when the Middle Assyrian Period began. In the following century Calah, the third major Assyrian city, was founded. Archaeological dates are more reliable beginning about 1114 BCE, with the accession of Tiglath-Pileser I (the one named in the Bible, in 2 Kings and the two Chronicles, was Tiglath-Pileser III). After Tiglath-Pileser II died and was replaced by Ashur-Dan II in 934 BCE, a more definite expansion of territory began, called the Neo-Assyrian Period, leading up to the the founding of the empire under Tiglath-Pileser III, who reigned from 744-727. The empire fell in about a decade, attacked by Babylonians, Medes, and a coalition of others including Elamites, all former provinces or tributaries of Assyria. It was all over by 609 BCE.

I found it fascinating that the mocking dirge over "the king of Babylon" in Isaiah 14 refers to the just-murdered Sargon II. Babylon at the time was a province of Assyria, and Sargon lived there. Although the author denigrates the theological understanding of Isaiah's lament, that verses 12-15 look through history to the fall of Satan, here called "day star" (Lucifer), this is to be expected of someone who takes the Bible as a literary work only. Christians believe that God uses the exclamations of His prophets to enlighten His people about matters such as this, without stating them directly. As Jesus stated, He used parables because "to you it has been given to know the mysteries of the kingdom of the heavens, but to them it has not been given." Jesus spoke in such a way that one had to ask Him a question to learn the interpretation. A similar reference to Satan in prehistory is found in Ezekiel 28:12-16.

While we are at it, the author also disparages the statement in Isaiah 37:37 that an angel killed 185,000 Assyrian soldiers, which prompted Sennacherib to return to Assyria. Perhaps it was the plague, he says, or some other sudden epidemic. He even considers that the same illness struck Hezekiah the Judean king. No Assyrian source mentions the destruction of about 2/3 of the Assyrian army. But none would! The kings only commissioned inscriptions lauding their successes. This goes for all the ancient kingdoms and empires. The author does mention that Sennacherib, who lived another 20 years until his sons murdered him (as the Bible notes), didn't send the army out for several years after returning from Judea. It's easy to conclude that he needed a couple of years to rebuild the army.

Whatever happened to the Assyrian army in 701 BCE is unrecorded by any source besides the Bible. We must recognize a principle of the miracles of God. If the Bible is true, and God created the Universe (whether 13+ billion years ago or something much more recent, as some believe, it makes no difference), then God is not a part of the Universe. What He does is not subject to the scientific laws that we have deduced over the centuries. Miracles have no "natural" explanation. People have for centuries tried to attribute things like the plagues in Egypt recorded in Exodus to sundry natural causes; some such as Immanuel Velikovsky posited fantastic scenarios such as Venus sideswiping the Earth before settling into its orbit (a process that would take billions of years, if it could occur at all). No such explanations are needed.

For such reasons, some Christians may be uncomfortable reading this book. It is best to take the phlegmatic attitude that Dr Frahm is a renowned scholar who happens to be a nonbeliever. His science is good. We can take his conclusions with a grain of salt, knowing he does not believe as we do. I am not threatened if he believes that one story or another is fictional. He has to believe that, really. I choose to believe the Bible. Assyria sheds light on things the Bible didn't mention, but not on the Bible itself. I enjoyed reading it a great deal, and I learned much from it.

Stories surrounding the rocks

 kw: book reviews, nonfiction, rocks, minerals, stories, legends, surveys

This is a shelf of my own Lapidarium (rock collection), chosen for its variety. If you click on the image you can see a larger version.

As a rock collector I have eclectic tastes. Here are minerals, fossils, sliced-and-polished geodes, and a few crystal clusters that were grown in a jar (such as the deep blue at bottom center: copper sulfate, which occurs in nature in very arid regions as the water-soluble mineral chalcanthite).

The word "lapidarium" is quite obsolete, but is found, very fittingly, in the title of a recent book, Lapidarium: The Secret Lives of Stones by Hettie Judah. Ms Judah writes primarily about art, particularly the stories surrounding artworks; here, the artworks are natural stones and modified stones.

Sixty stones, loosely so-called, are surveyed in six sections, with the themes Power, Sacredness, Evocativeness, Technology, Sculpture, and Life. Life? Consider Coral. In a game of Twenty Questions, the answer to the obligatory opening question, "Animal, vegetable, or mineral?" is "Yes" or "All". The polyp animal, bearing symbiotic algae in its tissues, secretes a mineral skeleton. The deep red skeleton of precious coral, so sought after by kings of old, is colored by pigments derived from the algae. You can only get away with this once.  The Life section also mentions Pearl and Blue Lias; the latter is a heavily fossiliferous shale on England's Jurassic Coast. A few examples from the other sections:

Power: Powerful people like gemstones such as emerald, ruby and sapphire. Note that ruby and sapphire are both corundum (aluminum oxide), with different minor impurities that confer their colors. So this is clearly not a mineralogy book. I firstly thought that Old Red Sandstone was an odd choice; it turns out that the famed Stone of Scone, where Scottish kings were anointed, is a big block of Old Red Sandstone.

Sacredness: Pele's Hair, a type of spun glass from volcanic lava fountains, is sacred to the Hawaiians. Sarsen is silicified sandstone (much tougher than the usual calcite-cemented sort) that makes up the larger stones at Stonehenge. Cinnabar, or mercury sulfide, is a bright red mineral that was used to make scarlet pigment for cosmetics and the clothing for royals and ecclesiastical officers (and poisoned a number of them). Tuff was used to form the Moai, the standing sculptures on Rapa Nui (AKA Easter Island). I must mention that, while the article mentions a study in 1997 of moving one of the statues using ropes, a sledge, and banana-juice lubricant, the moai actually "walked". See this 2013 video. It is a clip from a longer presentation.

Evocativeness (the section is called Stones and Stories): Lapis Lazuli, translated "azure-colored stone", was also a stone of power, but later became better known as the source of Ultramarine pigment for the intense blue and indigo colors in paintings of the great masters. Phonolite Porphyry is a "ringing stone" that makes up the substance of Devil's Tower in Wyoming. Tap a piece with a smaller stone and it will ring like a gong or bell. So will most of the Dolerite stones that make up the inner circle at Stonehenge, and there is a field of ringing stones in eastern Pennsylvania.

Sculpture: Gypsum (usually as alabaster), chalcedony, onyx, and crystalline quartz are among the stones favored for carving and sculpting into artworks. Red Ocher, a mix of red hematite and other iron oxides, may have been used for art tens of thousands of years ago, both as a pigment and as a material to sculpt.

Technology: Flint may be the basis of the oldest technology, that of making edged tools of stone by knapping; the article is mostly about a modern flint knapper who became so skilled, many museums have his counterfeits on display. Obsidian may be equally old, but its occurrence is not as widespread. Lodestone, magnetic ferrous (Iron II) oxide, appears to have a nearly 1000-year history as an aid to navigation. Coltan, an ore containing niobium (columbium) and tantalum, is still in heavy use for electronics. Mica, particularly the clear, colorless form called muscovite (named for Moscow), was used for oven door windows because it is heat resistant; in such a use it was called Isinglass.

This is a fun, well-written book, not about rocks per se, but about stories about rocks.

A survey of marine life with its own earworm

 kw: book reviews, nonfiction, marine animals, animal life, natural history, surveys

I wrote in the prior book review that a naturalist ought to be able to draw and paint. To write a book of natural history such arts are also necessary, and if one cannot self-produce the illustrations, one must have a good artist on call. Fortunately, Dr. Helen Scales was able to call on Marcel George to produce the lovely artwork in Around the Ocean in 80 Fish & Other Sea Life. The book is the latest in a series of "Around the World in 80" something (Trees, Birds, etc.). It also has kept a certain tune in my head for several days now! Here is the Bing Crosby rendition.

The suffix "& other sea life" is well put. Just for fun I compiled the non-fish:

• 16 mollusks, from octopuses and a squid to oysters, clams, snails and sea slugs
• 5 mammals, such as whales and dugongs
• 4 crustaceans, from krill to crabs
• 2 cnidarians: a coral and a jelly (AKA "jellyfish")
• 2 echinoderms: a starfish and a sea cucumber
• and one each sponge, siphonophore (Portuguese man-o-war), and annelid (segmented worm)

That leaves 48 actual fish. Each animal or animal group is depicted on a two page spread, such as this one for Parrotfish. This item has a little more text than usual; the average is one page of the two.

From time to time there is a full two page illustration, such as this one of nudibranchs, which are sea slugs, but there are a number of categories of sea slugs besides nudibranchs.

Considering that there are tens of thousands of fish species, around 100,000 mollusk species, and some 10,000 cnidarians, a book like this isn't even a "tip of the tip of the iceberg", but a smattering of things to entice our appetite for more marine natural history. The little articles are full of tidbits, such as the naming of the Ninja Lanternshark (Etmopterus benchleyi) by some 8-year-olds, because its lighting scheme makes it extra-sneaky; that many of the 60 species of flying fish can glide above the waves for several hundred meters and are as aerodynamically efficient as a hawk; or that the "bone" that stiffens the mantle of a cuttlefish is sometimes used in jewelry making.

And just by the way, cuttlefish display at least as much self-control as a human child in a marine version of the Marshmallow Test. Certain fish also pass the Mirror Test, recognizing that the image in the mirror is themselves. There's much more going on in the ocean than most of us could ever imagine. A book like this expands our imaginations, and I hope it leads some to learn more and further expand.

Bacteria hardly any of us know

 kw: book reviews, nonfiction, science, bacteriology, surveys

Behold the largest species (so far known) of bacteria. Thiomargarita namibiensis, the "sulfur pearl from Namibia", at 300 or more microns in diameter, can be larger than the smallest parasitic wasp, shown for comparison. It is visible without a microscope, being the size of the dot of a printed "i".

This is the first species of microbe described in The Curious World of Bacteria, by Ludger Wess (originally in German, translated by Jamie McIntosh). The author made many difficult choices to select just 50 species of Bacteria and Archaea for this book. Although Bacteria and Archaea are different domains of life, most of us, specialists included, usually use the term "bacteria" to speak of them all.

If they think of them at all, most people consider bacteria to be primitive life forms. Few realize that they have been subject to the same 4+ billion years of evolutionary history as every other kind of life on Earth. Most are less than 10 microns (or 0.01 mm) in their longest dimension. A few are smaller than 1 micron. But they come in a wide array of sizes and shapes.

Even more various are their metabolisms. Many species don't need oxygen—some are killed by it—and "breathe" sulfur or hydrogen plus carbonate, or even iron oxide. The author points out that life is energized by the transfer of electrons, by oxidation and reduction reactions. I learned a mnemonic in chemistry class: LEO & GER. LEO = "Loss of Electrons is Oxidation". Leo is the Lion, who says "Grr" (GER), which = "Gain of Electrons is Reduction".

When we use oxygen to oxidize chemicals in our bodies to get energy, the oxygen is reduced: Electrons move from some molecule to the oxygen. This rod-shaped bacterium, Desulforidis audaxviator, reduces sulfur instead of oxygen. The rod-shaped cells are about 5 microns long, but very narrow, 1/3 of a micron. This critter is found in deep mines, where some populations have been out of contact with Earth's surface for 25 million years.

Many folks only know about "bad" bacteria. By the way, the Archaea are not pathogenic. None of them. So all disease-causing "germs" are Bacteria. 

Certainly some great plagues have arisen from specific Bacteria. "The Plague", or the Black Plague, is possibly the most famous. The cause is Yersinia pestis, where "pest" means Plague in European languages. Like many bacterial diseases, these need a vector, or in this case, two vectors: The rat flea and the black rat.

The Plague changed the course of European history, twice, once in the late Roman Empire ("Justinian Plague") and once again some 700 years later. It still crops up here and there, and is a lot more deadly than COVID-19, but because of indirect spread (fleas+rats), it doesn't pose as much of a threat.

This is a book to read right through, as I tend to do, or to browse here and there for interesting articles. Either way, it's very well written and very informative. The author is young enough to write a few more books; maybe he'll pick another 50 (he has thousands of interesting species to choose among!) and write a sequel. Luscious thought!

All the little six-legs

 kw: book reviews, nonfiction, natural history, insects, surveys

Let's get some technical stuff out of the way first. There are 28 orders of insects. After the graphic, I'll explain a bit:

We all are familiar with most of the kinds of critters in the upper third of the diagram, and some of those in the left half. The "big four", that encompass about 80% of all insect species are the beetles, the butterflies and moths (butterflies are specialized moths), the true flies (including mosquitoes), and the wasps and bees and ants (bees and ants are specialized wasps).

What is an order? An order is a broad classification in the middle of the scale of taxonomy, which is the hierarchical "tree" of relationships. In brief, according to a structure first set in place by Carl Linné (Linnaeus) in 1758, the primary categories are these:

• Kingdom (the main ones in our experience: plants, animals, fungi, and bacteria. There are others)
• Phylum (all vertebrates are a phylum. Insects are in the phylum of arthropods, or "joint-legged")
• Class (major categories within a phylum. Insects are a Class. So are all the mammals, among the vertebrates)
• Order (mid-level categories within a class; differentiated by broad similarity of form and lifestyle. So all the beetles are in one class, Coleoptera)
• Family (lower-level categories within an order)
• Genus (a category for one or more similar species. One genus of butterflies is Danaus, and one genus of human-like apes is Homo)
• Species (the lowest category. A species is always appended to its genus, and such a binomial is always italicized. A human is Homo sapiens, and the monarch butterfly is Danaus plexippus. You probably know Tyrannosaurus rex, the big meat-eating dinosaur)

Now to the book: In 2918 the American Museum of Natural History published Innumerable Insects: The Story of the Most Diverse and Myriad Animals on Earth, by Michael S. Engel, a Research Affiliate of the Museum. It's a kind of coffee-table book, not quite as large as the usual coffee-table book. While there are lots of illustrations, there is plenty of explanatory text. The pictures are a treasure. The American Museum also houses one of the great collections of rare books on natural history, and this volume is illustrated with a few hundred selections from the past few hundred years of "insect literature".

For example, the artist Jacob Hoefnagel illustrated one of the first books devoted to insects, Diversae Insectarum by Claes Jansz, published in 1630 (The book's full title is very much longer).

This image is from the frontispiece of that book, showing just a hint of insect diversity. You can see about half the currently-known orders of insects represented here.

Innumerable Insects begins with a brief history of entomology, the study of insects. "Entomology" is sometimes used to cover related small many-legged things like ticks, spiders and scorpions, but they actually have their own fields of study.

There are about 1.6 million species of insects so far described. Depending on what is known about a species, the "description" is anything from a one- or two-page "letter" in a journal such as Nature to a many-page monograph that describes not only the morphology of the animal but its life stages and habits. It takes me about a minute to read the abstract on the first page of a journal article or letter. Just reading 1.6 million abstracts, so as to familiarize myself with all the known species, would take every waking moment (assuming 14 hours so I have time for meals and pit stops: 840 minutes/day) for 1,905 days, or 5 years and 11 weeks. I wonder how much I would retain… And this would only be possible if I had an army of assistants to run hither and yon, finding all of the descriptive letters and articles!

More than a third of insect species are beetles (the numbers in the tree above are a few years out of date). This illustration of sand beetles is part of a page from Biologia Centrali-Americana (An electronic version is available at the Smithsonian Institution). The volume on Insecta:Coleoptera was published in two parts in 1884 and 1887. The second chapter of Innumerable Insects puts this immense diversity in perspective. 

Moths/butterflies, flies, and wasps/bees/ants make up another third. Several chapters are used to introduce us to all the 28 insecct orders, one after another, grouped roughly by ecology and habit.

I was forcibly reminded upon seeing all the amazing illustrations that, prior to photography, a naturalist had to be an artist. The tradition continues, and it is still true that the best illustrations are drawn or painted rather than photographed. I particularly appreciate the Roger Tory Peterson Field Guides, with drawings that bring out the important features of every creature in a way a photograph cannot match.

The latter chapters introduce some special topics: social insects (ants, bees, termites, etc.); insect "languages", whether by sound or dance; camouflage; and pollination. It's well accepted now that pollinating insects—not just butterflies but also certain beetles, flies, and several others—co-evolved with flowering plants, and that this "collaboration" led to the very great diversity of both.

I had not expected so much fascinating information to be packed into a 200-page book that is about one-third pictures. Author Engel did a great job, presenting this all to us in such a digestible way. I am reminded of a much older book, Broadsides From the Other Orders by Sue Hubbell (1994), also about the insect orders. It has a bit of a different emphasis. The two books make great companion volumes.

And I could not close this review without showing at least one butterfly. This is Ornithoptera priamus, one of the bird-wing butterflies that enhance the beauty of the tropics. The illustration is from Natural History of Insects of India, by Edward Donovan, 1838.

VR and AR - Becoming the newest IE's

kw: book reviews, nonfiction, virtual reality, augmented reality, surveys, history

I must have been twelve when my family and I went to a Cinerama theater to see Windjammer. It was quite a special event, partly because it cost a lot more than going to an ordinary movie. The theater's program discussed what made Cinerama extra-special; the ultra-wide screen (more than 140°) and the fully-surrounding sound system. Though the movie had some kind of plot and plenty of action (mostly sailors-in-training climbing rigging, at least as I remember), the sheer spectacle was the main attraction. It was my first Immersive Experience (IE).

The hype surrounding Virtual Reality (VR) and Augmented Reality) AR—and several other bits of jargon that boil down to these two terms—promises us better IE's. So it is about time for a historical and technological survey of the VR/AR field, ably supplied in a new book by David Ewalt: Defying Reality: The Inside Story of the Virtual Reality Revolution.

The author digs deep into history for the forebears of motion pictures and TV, and various efforts, with varying levels of success, to immerse the viewer in the experience. Considering how prone we are to see animals and scenery in clouds, pictures on half-melted butter on a piece of toast, and maps and other images on Holstein cattle, it doesn't take much to prepare us to be immersed in whatever is going on in front of us. If you look now at a video made for "standard" TV (called NTSC), it seems surprisingly blurry. Although vertical resolution was 535 lines, horizontal resolution seldom exceeded 200 dots per line. A TV screen larger than 25" (diagonal; 20"x15") looked blocky. Yet we could easily become immersed in the action on the screen and "zone out" everything else, particularly in a darkened room.

Fast-forward through the two HD formats, which look good on bigger screens, up to 50" or so, and 4k, which comes close to the resolution that most people can see when the screen's horizontal dimension fills about 70° of their visual field (that means being about 50" from the center of an 80" screen). But our actual visual field is more than 200° wide by 150° high, and the zone of overlap for binocular vision is 120° wide. Thus, for a fully immersive visual experience, it takes a heck of an optical system!

Every VR system or AR system so far produced cuts into this, sometimes greatly. As described in Defying Reality, the Oculus Rift, first prototyped by Palmer Luckey nearly ten years ago (on sale for about 3 years now), comes the closest. It is almost exactly matched by the HTC Vive. Both claim 110° horizontal field of view, which is close to our stereo-vision field of 120°.

The author, as a journalist, had good access to Luckey and other developers throughout this recent history. He is a good subject for testing the equipment, because he is extra-susceptible to motion sickness. He bought a purported VR system 20+ years ago, got sick, and remained a skeptic about VR's possibilities until the Rift came along. That and a few equally recently developed headsets are the first ones he's been able to use without nausea. As we say in the computing field, "The iron didn't match the application" until about 2008. It takes computing power equivalent to a 1990's Supercomputer such as the Cray-YMP to do all the "physics" needed to keep up with our visual senses. A decent gaming computer (in the $1,500 price range, at the moment) now has that level of compute power.

More recent developments include the Magic Leap, the first capable AR system, that lets you see the world around you (through tinted glass, not by re-displaying video from external cameras), with virtual elements superimposed. It uses some amazing optical tricks to make that work. So far, though, the field of view of the Magic Leap system is only about 40°x30°, so it has some specialty uses, but is less capable of producing a full IE.

How soon will VR or AR be found in the average middle-class home? A lot depends on application development. It's a little like the year 1981, when the IBM PC was introduced. There wasn't much you could do with it at first, but by the end of the year, WordStar and Lotus 1-2-3 became the killer apps that pushed sales of the machines, even at prices exceeding $2,000 (or $3,000 if you got a 10-Mbyte hard disk). The $2,400 I spent on my first PC clone would come to $6,500 today. No killer app for VR or AR has arisen. When one appears, the field will attain some momentum.

David Ewalt is young enough to keep his finger on the pulse of the field for another decade or so, and write the next book, about how incredibly changed life is with such machinery in most homes, and perhaps in public spaces, trending toward a much better successor to the Google Glass (a great idea ahead of its time and far ahead of the tech needed to make it worthwhile). I'll keep a search agent out there for upcoming books by this author.