Tag Archives: science

In which Franklin learns what it is to be overwhelmed

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“Chaos is the score upon which reality is written.”
–Henry Miller

This post is likely to seem a bit disjointed and chaotic. (And long; deal with it!) This is as it should be; life these days has been a bit disjointed and chaotic. This is not necessarily a bad thing, mind; normally, I thrive on chaos. But every now and then, it’s kinda nice to have a break, y’know?

My mother has this saying that she used to use to irritate me with. Any time I complained about any element of my life, she’d look at me and say “It’s a consequence of your chosen lifestyle.”

She’s right, too.

On the nature of work

The company I work with (and I’m a minority partner in) has been, for lack of a better phrase, on the verge for many years now. The company makes a hand-held storm and lightning detector and tracker; it’s actually a pretty slick little gadget, which can detect lightning storms from about 75 miles away by the extremely characteristic EMP profile produced by cloud-to-ground lightning, and by virtue of a great deal of mathematical wizardry involving fast Fourier transformations and other big words, calculate the distance, speed and direction of travel, and ETA of the storm. It then tracks the storm right to the device.

The company has been desperately underfunded and desperately short of cash for the entire time I’ve worked with them; in fact, for about a year they couldn’t pay me regularly at all. They recently got some venture capital (not enough) and relocated to Atlanta, where they’ve been paying me more or less regularly a quantity that’s more or less sufficient to keep a roof overhead and food on the table.

Recently, they’ve encountered a problem that many startups face without being aware that it’s a problem: they’ve suddenly become too successful. We’re now selling gizmos faster than we can build them, in part because of a significant change in marketing strategy. In the past, these gizmos have sold to military, government, and commercial users; after all, these are the people likely to be left with their ass on the line in a sudden thunderstorm. You don’t want to be climbing telephone poles or cell phone towers with a storm on the way.

But now the gizmo has been picked up by retail resellers–something that we never thought would be significant, because focusing on home consumers never really seemed like much of a business opportunity.

And it’s going bonkers. We’re signing deals with retail chains left and right. Hammacher Schlemmer just bought an entire production run. And this is a problem, because producing more gizmos on very short notice is very expensive, and the fact that we’re selling these things so fast doesn’t mean we’re making money as fast; we don’t see the cash for 30, 60, or even 90 days. But we still gotta pay to build ’em up front.

Interesting times indeed.

On the nature of opportunity

When opportunity knocks, it’s always at the most inopportune of times.

For months, I’ve been working on a major revision to my sex game Onyx, which has been going quite slowly for a number of reasons, not the least of which are that this isn’t my day job, the new revision involves a total rewrite of very large sections of code, and the beta testers keep pointing out playability issues which I believe are valid.

Concurrently with this, I’ve also been working on an enormous revision to the Symtoys itself, which will see it become roughly ten times the size it is now and will also sport an entirely new look, as the current site is, to be blunt, appallingly ugly. The new site will have all kinds of kinky sex how-tos, tutorials on everything from rope bondage to improvised sex toys, and even a sex toy store.

Last week, I got an email from the editors of Playgirl magazine. They have a “do it yourself” how-to column, apparently, and in October they want to feature the Symtoys Web site in the column. Which is good, but the timing sucks, since I’m still depressingly far from having the site revision completed. Or if not “completed,” at least in a state where it can be uploaded and made live.

And on top of that, an interested party has offered me an advance on the book on polyamory I’ve been working on (but mostly not working on) for a while now. I really want to finish this book, and now I have a strong incentive to move it to the top of the List Of Things To Do.

I have a pile of proposed changes to the outline suggested by the editor I’d been working with; I need to dust off the files, make the changes, and get back into that again.

On automobile license tags

I’ve finally got ’round to doing things like registering my car in Georgia and stuff. I got some personalized license tags, for the first time ever:

The tag reads “H PLUS,” which only a small number of transhumanists is likely to get. It’s okay, though; the people who do get it are cool. 🙂

I love my little car…

On Links and Stuff

slouchinphysics, you’ll appreciate this one; it relates to the conversation we had last weekend about China surpassing the US as a center for research and technology. It’s an excerpt from a paper published in the 60s about particle physics in China, the prequel to which is a great example of what happens when science and political doctrine collide. But lest we think that the same sort of nonsense doesn’t happen over here: the Creationsits, unable to get their bullshit rubbish published in respected peer-reviewed journals, are trying to create a ‘peer reviewed’ journal of their own. (Props to 6-bleen-7 for the links.)

phoenixgeisha has proposed a challenge: create a CD of songs which, when heard by another listener, give the listener a sense of who you are as a person. I think this sounds like great fun.

Some other folks have created a programming language based on lolcats. Here’s Hello World written in lolcode:

HAI
CAN HAS STDIO?
VISIBLE “HAI WORLD!”
KTHXBYE

And finally, satellite view of contrail clutter left by passenger airline flights. This is an amazing picture.

On cats

Shelly was up over the weekend, and took the kitty Molly with her when she returned to Florida. Now figment_j‘s kitty liam is all I have left.

Liam and Molly didn’t much get along (or rather, Liam was madly, frantically in love with Molly, and Molly didn’t care much for Liam–its a good thing cats don’t feel heartbreak as acutely as people!), so the relocation of Molly was necessary.

I like having Liam. He reminds me of figment_j. The fact that all my relationships are long-distance now sux0rz.

Some thoughts on fatigue

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A long time ago, when I was going to school in Pennsylvania, I had a friend named Barry Kramer. Barry’s father is a machinist, and he gave Barry a metal rod, about a foot long and an inch or so in diameter, that had been mis-machined.

Barry used this rod (which weighed a good five or ten pounds) to beat things up–road signs, walls, pavement, that sort of thing. There’s something inherently, irrationally satisfying about holding a heavy piece of steel in your hands and really whacking the holy hell out of something…but I digress.

Anyway, one afternoon, a mutual friend of ours went over to Barry’s house, picked up the heavy steel bar, and delicately tapped on the ringer for the doorbell with it.

The steel bar failed instantly–it cracked in half and fell in two pieces to the floor.

I got to thinking about Barry this evening as I was leaving the office. I have a large laptop carrying case I’ve used for years; I’ve had it for so long it’s starting to come apart, and the strap is frayed. I walked outside and was just ambling along toward the car, minding my own business and thinking about cognitive limits and modeling of human intelligence, when I heard a distinct Tink! and the strap of the laptop bag went slithering over my shoulder, sending the bag plummeting to the ground.

I caught the bag before anything bad happened, and hauled it up expecting to see that the strap had failed. But no. The metal latch at the end of the strap had failed and split, very cleanly, in two.

Metal fatigue is really interesting. Most metals do not have an infinite fatigue life. In fact, with most metals, if you take a rod of metal capable of holding, say, 100 pounds of weight, bolt it to your ceiling, and hang a 90-pound weight from it, eventually the metal will fail and the weight will fall. Titanium doesn’t behave this way, but many other metals do.

The split where the metal latch failed is surprisingly clean. The metal broke precisely in an almost perfectly straight line; the geometry of fatigue failure is not fractal, which isn’t what I would expect.

But goddammit, now I have to buy a new laptop case.

So what does it mean to succeed?

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If you’re a printer, or you’ve ever been in the print industry in any capacity at all, or you’ve ever taken a design class, or even if you’ve ever used the “random text” command in any of a large number of different programs, you’ve probably seen a piece of gibberish text that begins with the words “lorem ipsum.” Since the dawn of time, relatively speaking, that gibberish text has been used by newspaper editors, magazine layout artists, prepress people, designers, even Web designers, as “filler” text to let them see, for example, how many columns of type they need, or whatever. The whole text looks like this:

Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut laoreet dolore magna aliquam erat volutpat. Ut wisi enim ad minim veniam, quis nostrud exerci tation ullamcorper suscipit lobortis nisl ut aliquip ex ea commodo consequat. Duis autem vel eum iriure dolor in hendrerit in vulputate velit esse molestie consequat, vel illum dolore eu feugiat nulla facilisis at vero eros et accumsan et iusto odio dignissim qui blandit praesent luptatum zzril delenit augue duis dolore te feugait nulla facilisi. Nam liber tempor cum soluta nobis eleifend option congue nihil imperdiet doming id quod mazim placerat facer possim assum. Typi non habent claritatem insitam; est usus legentis in iis qui facit eorum claritatem. Investigationes demonstraverunt lectores legere me lius quod ii legunt saepius. Claritas est etiam processus dynamicus, qui sequitur mutationem consuetudium lectorum. Mirum est notare quam littera gothica, quam nunc putamus parum claram, anteposuerit litterarum formas humanitatis per seacula quarta decima et quinta decima. Eodem modo typi, qui nunc nobis videntur parum clari, fiant sollemnes in futurum.

That’s the full version. That, or fragments of it, are used whenever someone has a need for nonsense text to fill in a blank area in a design, until the real text comes along.

Problem is, that nonsense text is not nonsense.

In the groundbreaking book The Selfish Gene, Richard Dawkins put forth a revolutionary new way to conceptualize evolutionary biology–at the level of the gene, not the level of the individual. A gene’s “goal,” in a manner of speaking, is to reproduce itself. Genes that do this efficiently succeed and become widespread; genes that don’t, disappear.

Many people still have a mistaken view of evolution as “survival of the fittest.” Charles Darwin never used that expression [Edit: Charles Darwin did not use the expression until the fifth edition of Origin of Species, where he adapted it as it had come to be associated with his ideas of natural selection through Spencer’s deliberate creation of an analogy between evolution and market economics using the term)–it was coined by a man named Herbert Spencer–and the term can create inaccurate perceptions of how evolution works. Evolution does not necessarily work on the level of the individual at all; for example, all the bees in a beehive save the queen are not capable of reproducing, and so have no chance to pass on their genes. However, all the bees in a beehive share their genes with the queen. So if a bee dies, but its death helps promote the survival of the hive, that particular bee’s genes survive; it is the survival of the gene, not the survival of the organism, that matters.

In many cases, the survival of the organism means the survival of the gene–in many cases, but not in all. And some genes are passed on by individuals who do not express those genes at all. Male pattern baldness and red-green color blindness in humans are passed on matrilineally–you inherit those genes from your mother–even if they are expressed primarily in men. If you were somehow to prevent every color-blind man or every bald man from reproducing, even though color blindness and male-pattern baldness are genetic, you would not remove those genes from the population.

The human genome project is attempting to map and understand every gene that makes a human being. Each of these genes codes for the production of a single protein, and each of these proteins is responsible for carrying out all the tasks necessary to build a cell and make it go. Human beings have somewhere around 25,000 genes, each made of many DNA base pairs; the ntire sequence of these genes has been mapped, and their function is being explored.

And a lot of them are gibberish.

Biologists call this “junk DNA”. It exists in all species over a certain level of sophistication. Some of it is “obsolete code”–stuff that calls for things the organism no longer needs or uses, like gills and tails in humans. Some of it has been selected against because the stuff it codes for has no or negative survival value, at least in the short run. (New research suggests that mammals carry the genes that would let them, and us, regenerate damaged organs or regrow lost limbs, but that these genes are switched off. If that’s the case, learning how to switch those genes on could revolutionize medicine…but I digress.)

Some junk DNA is old or obsolete…but some is not. A good deal of this “junk DNA” is actually the remnants of old retroviruses, viruses that eons ago infected our ancestors and then became inert, their DNA integrated with ours.

Retroviruses are strange beasts. They work in a simple but devious way. They contain a strand of RNA, not DNA, and this strand of RNA has the necessary code for creating a special enzyme called “reverse transcriptase,” bundled together with the viral code.

When the virus attacks a cell, it injects its RNA into the cell. The RNA is snapped up by tiny machines within the cell whose job it is to read pieces of RNA and build the proteins that the RNA calls for. These machines have no way to tell that a particular piece of RNA is legitimate; they read and process any RNA they see. The viral RNA, once inside the cell, gets read and processed just like any other RNA.

The viral RNA tells the machines to build reverse transcriptase. Reverse transcriptase is a molecular machine that take a piece of RNA and writes it into the cell’s own DNA. When a retrovirus infects a cell, it injects its genes. Its genes tell the cell to make reverse transcriptase, and once the cell does that, the reverse transcriptase writes the viral RNA into the cell’s DNA; the viral gene becomes a part of the cell’s gene.

Now, normally, at this point the viral gene pretty much shuts down the rest of the cell, and tells the cell to stop whatever it was doing and dedicate all its resources to making more copies of the virus. This destroys the cell, of course, but it’s how viruses reproduce.

Every now and then, though, something goes wrong. The viral RNA is injected, the reverse transcriptase is made, the viral genes get recorded into the cell’s own DNA, and then…nothing. The viral gene just sits there. It doesn’t activate, it doesn’t take over the cell, it just sits there.

But when that cell divides, the viral gene goes with it. that viral gene is now a permanent part of the cell’s DNA. Sometimes, if a gamete is infected, the viral DNA gets passed on to new offspring; it never actually does anything, it’s just along for the ride. Has it succeeded? If it never gets activated, ever produces anything, but the organism it infected becomes successful and spreads all troughout the world, then that viral gene has been spread throughout the world too, right?

In talking about ideas, philosophers often speak of “memes” rather than “genes.” A meme is an idea; memes–ideas–can spread themselves, and can grow. You can look at Christianity as a meme, for example. People who accept the idea of Christianity want to spread that idea; the idea uses their minds, just as a viral gene uses a cell, to spread and reproduce itself. Christianity is a very complex meme, which has fractured and divided into competing sub-species, and most memes are not that complex, but it’s a good example nonetheless.

So what’s the equivalent of a “junk meme?” Lorem ipsum.

Most people believe that the Lorem Ipsum text is meaningless gibberish. In fact, “lorem ipsum” is a generic term for any gibberish text in the print industry–“Oh, I don’t have Sandy’s editorial yet, so I just put some lorem ipsum into the space where her column goes for now.” But the lorem ipsum text is not meaningless, and it’s not gibberish.

In fact, the lorem ipsum text is Latin, and it comes from a work called De Finibus Bonorum et Malorum (The Extrmes of Good and Evil), a study on ethics written by the philosopher Cicero in about 45 BC. The fragment that survives as the modern gibberish text placeholder begins not only in the middle of a sentence, but in the middle of a word; the complete section of the original text begins

Neque porro quisquam est, qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit, sed quia non numquam eius modi tempora incidunt ut labore et dolore magnam aliquam quaerat voluptatem. Ut enim ad minima veniam, quis nostrum exercitationem ullam corporis suscipit laboriosam, nisi ut aliquid ex ea commodi consequatur? Quis autem vel eum iure reprehenderit qui in ea voluptate velit esse quam nihil molestiae consequatur, vel illum qui dolorem eum fugiat quo voluptas nulla pariatur?

Translated into English, the passage reads:

There is no one who who loves pain itself, who seeks after it and wants to have it, simply because it is pain, but because occasionally circumstances occur in which toil and pain can procure him some great pleasure. To take a trivial example, which of us ever undertakes laborious physical exercise, except to obtain some advantage from it? But who has any right to find fault with a man who chooses to enjoy a pleasure that has no annoying consequences, or one who avoids a pain that produces no resultant pleasure?

One could argue that, viewed from a certain perspective, this passage represents a meme that is successful almost beyond all reason, because it has been picked up and reproduced over and over and over again. But like the viral gene that becomes an inert, non-functional part of its host’s DNA, this meme is “junk;” it is completely inert, and most people do not even realize it has any meaning at all. It’s filler; it’s treated as gibberish, just like the viral gene is effectively gibberish.

But is it successful? It’s picked up and propagated all over the planet; it has spread far and wide, as inert viral genes which have become a part of the human genome have spread far and wide; but is it successful?

Because it cannot be said enough…

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…especially in modern-day America, currently in the grip of a wave of anti-intellectualism and a backlash against reason and logic that’s quite remarkable, and depressing, to behold:

I wish to propose for the reader’s favorable consideration a doctrine which may, I fear, appear wildly paradoxical and subversive. The doctrine in question is this: that it is undesirable to believe a proposition when there is no ground whatever for supposing it true. I must, of course, admit that if such an opinion became common it would completely transform our social life and our political system: since both are at present faultless, this must weigh against it.

— Bertrand Russell, On the Value of Skepticism, 1935.

In which we learn that Franklin is disrespectful

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A short time ago, a lengthy and near-incoherent ramble about the dawning of a new age of divine government appeared in my inbox. This email was posted on an email list to which I belong, though not, to be fair, by choice–I was subscribed to the list by its owners without my knowledge. Anyway, I posted a rather lengthy reply poking fun at the original message, which was laced with absurdities galore.

One of the people on the email list responded quite angrily. She does not subscribe to the same…ahh, peculiar beliefs as the original poster, nor does she much seem inclined to believe in the coming of the Divine Government, but she was very angry nonetheless. She called me a long list of names, in fact, while saying that all beliefs should be treated with respect.

The list of names itself is not particularly interesting. Nor is the unconscious irony in the notion of a belief system that says all ideas should be treated with respect, and anyone who disagrees with this idea should be called names. Nor, really, is her apparent inability to distinguish between mocking an idea and mocking a person; many people have difficulty differentiating the two, and will often respond to an attack on their ideas as though they had personally been attacked.

What is interesting, though, is one of the names she called me. In with the list of other names was one that is absolutely on the mark. “Disrespectful,” she called me. And she’s right; I am.

The notion that all ideas deserve respect doesn’t hold much value to me. Even the notion that all spiritual ideas deserve respect doesn’t much agree with me; there are many spiritual ideas–for example, the notion that the world is hollow and populated by a race of aliens or superbeings (depending on the particular theory being presented) who will once again rise to reassert the primacy of the Aryan race…and no, I’m not making this up…doesn’t command much respect from me. Nor do spiritual beliefs such as the more extreme flavors of Christian Dominionism (some of which assert that whites are God’s chosen people) particularly deserve respect.

Now, does that mean spirituality as a whole is open to ridicule?

Not necessarily. The fact that human beings are spiritual animals sems written into our genes. Spiritual beliefs, properly applied, are not falsifiable; they make assertions which can not be tested, and which are impossible either to prove or to disprove. I don’t necessarily find all nontstable assertions absurd. For instance, the observation that certain constants (such as the speed of light, Planck’s constant, and so on) appear written into the fundamental laws of physics, and that if these constants were to change by even the tiniest amount the physical universe would not be possible, has led some people to assert that these constants were set by a creator divinity. This is a fundamentally untestable assertion, and I don’t spend any time ridiculing it; I’m actually neutral on whether or not it’s true, and have no opinion one way or the other on the existance of such a creator divinity.

But here’s the thing. Assertions of empirical fact are notthe same as assertions of spiritual belief, and when you make an assertion of empirical fact, now you’re playing with the big boys.

When you play with the big boys, you play by big-boy rules. When you make an assertion of empirical fact, now everything changes. Assertions of empirical fact do not get or deserve automatic respect. Assertions of empirical fact are evaluated by a ruthless meritocracy. They live or die by only one criterion–how closely they match the physical universe. All assertions of empirical fact start with zero credibility; they gain respect by matching observations of the physical universe, and lose respect by failing to match observations of the physical universe.

Some assertions of empirical fact are rooted in, or motivated by, spiritual beliefs. And sometimes, those who hold spiritual beliefs seek to have it both ways.

In the article Snake Oil and Holy Water, Richard Dawkins (a hero of mine) lays it out pretty succintly. Religion and spirituality, we’re told, inhabits one sphere of human thought, and observation of the physical world occupies another; you can not judge spiritual beliefs by scientific principles. And that’s true, as far as it goes. But what happens is that people who advocate spiritual beliefs make assertions about the physical world–assertions which, quite often, turn out to be wrong–and then when called on it, retreat into “You can’t judge me! You can’t tell me I’m wrong! You must respect my beliefs; spirituality is not the same thing as science!”

You can’t have it both ways. If you want to talk about spiritual beliefs, you can’t make assertions of empirical fact. If you do make assertions of empirical fact, you can’t then retreat into spirituality when you are called on any errors or fallacies in those assertions of empirical fact. If you want to play with the big boys, you have to play by big-boy rules.

The rambling New Age missive to which I replied looks like a statement of spirituality, but it’s not. It’s a statement of empirical facts–many of them, in fact. It asserts that on such-and-such a date and time, the world will be exposed to a beam of ultraviolet light, and that this light will originate with “the fifth dimension.” We have detection equipment capable of responding to ultraviolet light; if this assertion is true, it’s easy to test. It asserts that this beam of ultraviolet light is “highly charged,” which betrays a profound ignorance of the nature of ultraviolet light; photons have no rest mass and no charge, and thus a beam of light can not be “highly charged” by definition. It asserts that this beam of light will begin at the same time in all time zones and last for seventeen hours–an impossibility, as wolfger pointed out, because all the time zones span twenty-four hours.

And, most remarkably, it makes assertions about the way this beam of light will affect human beings, claiming that its presence will affect human behavior in very dramatic ways.

I have written before about the tendency of the human brain, when faced with a new idea, to fail open and default to accepting the idea rather than challenging the idea. This is a tendency I think it pays to be aware of, and I have developed the habit of “watchdogging” myself whenever I read an article or hear a story or see a new idea. I’ve sort of set up an informal hierarchy, which I use to determine how much credence should be accorded some new idea.

At the top of the hierarchy are ideas which agree with current theory, are supported by a large amount of empirical evidence, and are consistent with existing models of the way the universe works. Such an idea is not necessarily true, of course; but it is more likely to be true than ideas that don’t meet these criteria. It is true that existing models are incomplete and existing knowledge of the universe does not extend to everything; however, that does not invalidate these criteria. When Einstein came along and constructed new models which seemed to make Newton’s laws of motion obsolete, it’s important to understand that Einstein’s models extended our understanding into situations where Newton’s models don’t apply, but that Einstein’s models and Newton’s models make the same prediction when applied to, say, what happens when you throw a baseball. And they have to, because we already know that Newton’s models are smack-on when applied to baseballs. If someone comes along and proposes new laws of motion, they damn well better agree with Newton about what happens if I throw a baseball, too, because I’ve already seen that Newton gets it right. His model describes reality; any model that disagrees with his, doesn’t.

Next level down comes ideas that seek to extend current ideas or to propose new systems where current ideas don’t apply, but which are unsupported by empirical evidence; or ideas which are consistent with current models and current understanding, but for which evidence does not exist. The notion that there is life on other planets is a great example. It violates no laws of physics, it is consistent with our current working knowledge of the physical world, and indeed it seems quite likely given our current knowledge of the physical world–but it’s unproven.

Working farther and farther down the chain means getting closer and closer to ideas that are absurd or ridiculous on their face. Ideas which are not internally consistent, ideas which disagree radically with current knowledge about the physical world, ideas which make predictions radically at odds with observations of the physical world, and ideas which do not follow from their own premises are all ideas which do not deserve initial respect. The more an idea diverges from empirical observations of the physical world, the more an idea contradicts its own premises or its own assumptions, the harder that idea had better work if it wants to be accepted. Extraordinary claims require extraordinary proof. Eventually, an idea becomes so absurd that I feel confident in ridiculing it. And, sensibilities of the woman on the mailing list aside, ideas so absurd, so internally inconsistent, and so far out of line with the physical world as this New Age nonsense about ultraviolet light and divine governments deserve ridicule. This idea made statements of empirical fact that were manifestly untrue, as evidenced by the fact that it is now October 23rd and the world looks pretty much the way it did on October 17th, save for a few small details–the number of people dead in Iraq, the number of days left until George Bush is no longer in office, the number of times I’ve mistakenly left my cell-phone charger somewhere.

Ideas do not deserve automatic respect. There is no shame in calling “bullshit” on bullshit ideas. In fact, I submit that calling bullshit is the duty of anyone anywhere interested in truth. Truth comes only from the open and vigorous competition of ideas, and ideas which do not match reality in this meritocracy give way to ideas that do. We advance as a species by separating wheat from chaff, by testing ideas for weakness and inconsistency and discarding those that don’t measure up. An assertion of empirical fact that matches observed reality is superior to an assertion that does not; respect is earned, not automatic. Spiritual ideas exist in a sandbox, isolated from objective reality and not subject to the same rules as statements of empirical fact–but as soon as they leave that sandbox, they better be prepared to compete on their own merits, and that means being subject to inspection, and to scorn and ridicule.

Disrespectful? You bet. If you want my respect, you have to earn it. Learning about time zones is a good place to start.

It’s official…

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…Pluto is not a planet any more. Apparently, size does matter.

About time, too. Pluto lacks the basic characteristics of the other planets–or, at least, it looks a whole lot more like a bunch of other debris orbiting around beyond Neptune.

People have always gotten Pluto wrong since the get-go. When i was in grade school, I remember a mechanical model of the solar system we had in my science class, with a light bulb for the sun and little metal balls for all the planets. They were all linked together and geared so that the planets whirled around the sun when you spun the whole gizmo.

Problem was, it showed Pluto’s orbit as circular and in the same plane as the other planets. Even at eight years old, I knew that was wrong. Later, when I was in high school, I successfully trapped my science teacher by asking him to name the planets in order from the sun. He recited the familiar liturgy–Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto. However, Pluto’s highly erratic orbit takes it inside that of Neptune; at the time, it went Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Pluto, Neptune.

And now, finally, saner heads have prevailed and the world’s astronomers have decided that Pluto is not a planet after all. Which is good; allowing Pluto as a planet would mean allowing a half-dozen other rocky bodies–or more!–as planets, too.

The only real question left, at this point, is the most important one: how will this news affect the box office receipts for Snakes on a Plane?

Some thoughts on blowing up airplanes

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So, unless you’ve been living under a rock lately, you probably already know that a bunch of British terrorists were recently arrested for plotting to blow up a bunch of airplanes bound for the US using explosives mixed together from various liquids smuggled aboard in drink bottles. In fact, even if you have been living under a rock, it’s still pretty tough to get away from all the “news” on the topic; and airlines are now banning any “liquids, gels, or creams” from being brought on board.

What you probably don’t know is that the entire plot is a load of crap that would not have worked even if the terrorists had boarded the plane.

See, here’s the thing.

Supposedly, the terrorists had planned to whip up a batch of triacetone triperoxide, a highly unstable compound that tends to go “bang” if you heat it, jar it, or look at it crosseyed. Now, this stuff is for real, and yes, it does go bang, and yes, you can mix it up from chemicals you can get fairly easily, like hydrogen peroxide and sulphuric acid. But it’s not just a question of mixing the chemicals together and making a bomb; it doesn’t work that way. physicsduck might be able to do it; a bunch of random religious fanatics without the brains to pick their noses, much less blow up a plane–not.

Synthesizing TATP takes several hours under carefully controlled conditions. If you mix it too fast, or too hot, it smells really bad and then blows up in your face, but not with very much force–you might injure yourself and if you’re remarkably clumsy you might even kill yourself, but you’re not going to bring down a plane. (Bringing down a plane is rather more difficult than people realize.) Creating enough TATP to actually blow up an airplane is not the kind of thing you can do in a makeshift lab or, say, an airplane bathroom.

That’s not the interesting part, though. Blind hysterical panic and hand-wringing over some largely illusory threat, followed by political pandering for power and stupid, pointless “security” measures that don’t actually make anyone any safer but do admirably at diverting attention from real weaknesses in airline security that’d be just too expensive to fix–none of that is interesting at all. What is interesting is triacetone triperoxide.

I like triacetone triperoxide. I like it for two reasons–first, because it belongs to a class of explosives called “entropic explosives;” and second, because it’s used to make a type of toy called a “whippersnapper”–a little twisted ball of paper about as big as your fingernail that goes bang when you throw it on the ground or step on it.

I used to buy boxes of whippersnappers when I was a kid. They’d come 25 little sperm-shaped paper snappers to a box, packaged in sawdust, and I would hide them in my sister’s room so that they’d bang when she walked into her closet or open her dresser drawer. (Yes, I was a very, very bad kid. When I got bored with that, I’d rig old-fashioned flashcubes to a battery using a variety of improvised triggers, so that there’d be this dazzling flash of light when she opened her jewelry box or otherwise least expected it…but I digress.) I haven’t seen any whippersnappers in stores in a long time, but I’m told they’re still available, only now they’re called “snap and pops” or something.

When TATP goes bang, it’s called an “entropy explosion.” I shit you not. It doesn’t explode by rapid oxidation like other explosives do, and it doesn’t produce any heat to speak of; the explosion is not vigorously exothermic, and it does not end up in an energy state that’s very much lower than the state it began in. Instead, the force of the explosion results from the very rapid (and sometimes spontaneous) decomposition of the solid to a gas. This decomposition doesn’t produce much heat, but it does liberate tremendous amounts of entropy.

Now, I have mixed feelings about entropy. But I do have to admit that the fact that you can actually make an entropy bomb is pretty damn cool.

Some thoughts on entropy

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It seems like I spend most of my life in a constant, never-ending battle against entropy, the tendency of all natural systems to progress toward a state of increasing disorder.

Yesterday, Shelly and I spent a good deal of time cleaning up the living room. I’ve moved a great deal of the stuff that used to be in my office into the apartment–eight years’ worth of business records, files, several computers (including a G4 Cube, arguably the most beautiful computer ever designed), and all the other stuff that accumulates when one spends time in one place for an extended period of time.

I hate entropy. The second law of thermodynamics says that energy will, whenever possible, seek to become disbursed. The net total sum of entropy in any closed system–such as, for example, the universe–always increases; stars burn out, iron rusts, people age and die.

And frankly, it all pisses me off.

It seems to me a damn poor way to run a universe–build into it an immutable natural law which guarantees, in the end, the heat death of that universe and everything in it.

Put most simply, entropy is energy, but it’s energy that can’t be used for anything. The total amount of entropy in a system is generally represented by the letter S; the relationship between entropy and energy is given by the equation

where delta-S is the change in entropy in the system, q is the amount of heat absorbed by the system, and T is the absolute temperature of the system at the time the heat was absorbed. As a system absorbs heat, the entropy of that system increases.

Certain processes in the universe are said to be “thermodynamically irreversible.” What that means, in its most basic form, is that certain changes in a system which result in increased entropy will not spontaneously reverse themselves. (It’s a bit more complex than that, of course; thermodynamically irreversible processes will reverse themselves, and that reversal itself is thermodynamically irreversible, if the environment changes in such a way that the reversal of the process increases entropy. But I digress.)

The notion of thermodynamic irreversibility is an important one. It means that, barring a change in the surrounding environment, certain processes once run will not revert back to their initial state. The universe tends toward a state of increasing entropy; a process that increases entropy isn’t going to go back on itself.

Consider a baseball lying on the ground. If you were to make a movie of how that baseball came to be lying on the ground–starting from a pitcher’s hand, flying toward a batter, striking the bat, zooming up into the air, falling back toward the ground–and then you were to play that movie backwards, you would not see anything that violates the laws of physics. The ball could start on the ground; then, all the air molecules around the ball could suddenly conspire to strike the ball in just exactly the right way to increase its kinetic energy, flinging it up from the ground and accelerating it toward the batter. The ball could strike the bat, where most of its energy would be absorbed by the bat and from there by the batter, the muscles in his arms taking that energy and dumping it into molecules of water and carbon dioxide, turning them into glucose molecules. Slowed and with its trajectory altered, the ball could go flying toward the pitcher, where his muscles absorbed the remaining kinetinc energy, turning it into chemical energy by combining water and carbon dioxide and storing the energy in the molecular bonds of the glucose his muscles created.

It could happen that way, but it doesn’t. This sequence of events would require a rather startling decrease in entropy–the random disorganized molecules of air suddenly conspiring together to move in just the right way to propel the ball, the ball-s trajectory taking it precisely back to the bat, the muscles in the player’s arms absorbing kinetic energy and storing it in glucose molecules…

It doesn’t happen that way because all these processes are thermodynamically irreversible. A ball flying through air will collide with the molecules in its way, which will absorb some of its energy and go rocketing off in random directions, generating heat and friction that slow the ball down; this increases entropy. The air molecules aren’t going to spontaneously move to a more highly ordered state, and push against the baseball in just the right way to speed it up; this process reduces entropy, and a reduction of entropy in one place can not happen unless it’s offset by a greater increase in entropy somewhere else.

My first exposure to entropy was in a college physics class, where we discussed the relationship between the ideal gas law, PV=nRT, and entropy. If you take a container of gas at high pressure, and you open the top of that container, the gas escapes until the pressure inside the container is equal to the pressure outside the container. If you open a container and leave it sitting in a room, the air in the room will not spontaneously start pouring into the bottle until the pressure inside the bottle is greater than the pressure outside the bottle. When the pressure inside and outside the bottle is equalized, the entropy in the system is at its maximum.

Each individual molecule of air is bouncing around totally at random, but the probability of all the molecules ending up in the bottle at the same time is very low indeed. As each molecule bounces around at random, the total net probability that any one molecule will be in any one place is pretty low, but the total net probability that the number of molecules in one place will be the same as the number of molecules in another is very high.

This is important, because there is a relationship between entropy and probability. In a gaseous system, if the system has two different states that it can be in, and the probability of the less probable state is given by P and the probability of the more probable state is given by P’, then the entropy in the system can be determined by

where R is the universal gas constant and N is the number of molecules of gas. More generally, in any kind of system, (R/N) will be replaced by some kind of constant, whose value depends on the particulars of the system.

That is, the entropy of a system increases when its state changes from a low probability condition to a high probability condition.

Now, let’s consider a universe without entropy. Entropy provides a mechanism by which certain changes are thermodynamically irreversible; the system favors one state over the other, and changes that increase entropy won’t spontaneously revert. But what happens without this mechanism?

All the structures that exist in the universe today are the result of the gradual accumulation of small changes over time. The initial state of the universe was uniform; the processes that caused non-uniformities to exist, that caused molecules of hydrogen to form, that caused those molecules to congregate and gravitate and form stars, that caused those stars to fuse heavier elements and burn out and explode, that caused the debris from these explosion to accumulate and form new stars…all these processes are thermodynamically irreversible. Some of these processes did result in spontaneous localized increases in order and decreases in entropy, to be sure; but the net sum total of entropy in the universe increased at every step. (Creationists always try to argue that thermodynamics means the spontaneous emergence of highly ordered living things, and the spontaneous increase in the complexity of those living things, is impossible; what the Creationists don’t get is that entropy always increases in a closed system, but this planet is not a closed system. Increase in order is permissible, if you add energy to the system; but adding energy to the system increases entropy somewhere else. The sun is an enormous maw of entropy; the decrease of entropy in living things here is more than offset by the increase in entropy there.)

So without entropy, there’s no mechanism for these small changes to accumulate. Without entropy, the changes that result inexorably in the formation of stars and planets and iPods and you and I aren’t irreversible; the system tends toward a steady state, with each change equally likely to be reversed.

So in other words, without entropy we wouldn’t be here. Without that ratchet that lets changes happen but then prevents them from un-happening, the universe doesn’t do anything interesting.

Which means I shouldn’t really resent entropy as much as I do. But dammit, it still seems like a poor way to run a universe to me. A universe that doesn’t run down and end in heat death, but doesn’t do anything interesting, or a universe that does marvelous and interesting things, then sputters out and dies…man, I want another choice!

Today’s mission, should you choose to accept it…

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Shelly challenged me with this one a while ago, and I was just reminded of it by a conversation in IM.

Let’s say that you suspect that you are living inside the Matrix–that is, the reality into which you were born and in which you and everyone else lives is a simulation.

Would it be possible, using only the tools and observations you have available within that simulated reality and without any referent to anything outside the simulation, to demonstrate conclusively that you were living in a simulation? And by the same token, would it be possible to demonstrate, if it turned out that you were not living inside the Matrix, to demonstrate that you were not? If so, how?

Got me stumped. Ideas?

Link o’ the day: Robots and Slime Mold

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Courtesy of zaiah: Robot Moved by a Slime Mould’s Fear. (datan0de, you’ll get a kick out of this one!)

A bright yellow slime mould that can grow to several metres in diameter has been put in charge of a scrabbling, six-legged robot…

Physarum polycephalum is a large single-celled organism that responds to food sources, such as bacteria and fungi, by moving towards and engulfing it. It also moves away from light and favours humid, moist places to inhabit. The mould uses a network of tiny tubes filled with cytoplasm to both sense its environment and decide how to respond to it. Zauner’s team decided to harness this simple control mechanism to direct a small six-legged (hexapod) walking bot. […]

Biology is already influencing the evolution of robots in other ways. For example, researchers led by Chris Melhuish at the University of the West of England in Bristol, UK, have developed robots that generate power by consuming flies.
“Computational autonomy has been studied for some time,” says Ioannis Ieropoulos of the University of Western England team. “For a truly autonomous robot, the level of computational complexity will depend on the available energy.”