Science Plays Come of Age

“I’m too creative to do astronomy.” That was the line used, in all seriousness, by a student I once had in an astronomy lab course. The lab in question involved learning about the motion of the planets around the Sun. “If I could just write a play instead of doing the lab, I’d be fine.” Well, I replied, if you write a play demonstrating that you understand Kepler’s laws of planetary motion, and have students in the class perform it, I’ll be happy to give you full credit for the lab.

Lauren Gunderson Sadly, the requested play never materialized, as I suspected it wouldn’t. But happily, in a similar set of circumstances Lauren Gunderson responded very differently, as she explains in an article in The Scientist:

My career as a science playwright started when I asked my undergraduate physics professor to let me write a play instead of a term paper. Luckily he agreed, and the result was a time-twisting play called Background, based on cosmologist Ralph Alpher. Unexpectedly, the play not only satisfied my physics professor, it went on to receive awards and inspire productions across the country.

Lauren is a young playwright (and author of the occasionally-updated blog Deepen the Mystery) specializing in plays with scientific themes. She’s not the only one, of course; it’s become quite the cottage industry, these science plays. As Dennis Overbye put it at a conference in Santa Barbara, “Is anyone writing plays that aren’t about quantum mechanics any more?”

I’d be happy to summarize Lauren’s article, but she puts it better herself:

But what does it take to write a good science play? As a playwright, I believe in communicating science effectively, but not taking out what makes science hard. So it is absolutely essential to learn the relevant science well enough to represent it accurately — otherwise the whole play fails. I always do a lot of research from online magazines, scientists’ Web sites, and books on history and theory — everything from Brian Greene’s books on string theory to Newton’s Principia itself has passed across my desk. And many playwrights, myself included, consult scientists in person for critique, advice, and content.

In a science play, you want to make your scientists sound like real scientists. I’m not afraid to use a lot of jargon — I sometimes use what I call the “verbal wall of science” effect, in which I allow a character to speak freely like a scientist, without any further explanation. This isn’t to confuse a general audience, but to allow an appreciation of the character’s expertise. Yet I also try to combine effective science with effective poetry to create something that is true both in the concrete and the abstract. Science metaphors work best this way. For example, the particle physicist in my play Baby M explains her work this way:

We move in secrets. Fundamentals locked, related in code. What is obvious is not always what is. And what is isn’t always what is known. Essentially, we deal in thought made manifest, and this work represents the world.

The best scientific characters do all the things that make us human, not just the things that make us brilliant. So it is not enough for me to show you scientists doing science; I need to show you why they do it. Why do they venture into the essence of nature? Why do they subject themselves to deadlines and peer reviews and failure?

Okay, we wish that most scientists spoke as eloquently about their work as Lauren’s character does. But the point remains: if you’re going to have scientific themes, it’s worth the effort to get the science right, and — perhaps even harder — to get the attitude and language of the scientists right. Nothing different than would be expected if you were writing about lawyers or doctors.

Last year I gave two “literary lectures” at local theaters that were putting on plays with science themes. The first one was a production of Charlotte Jones’s Humble Boy
at Remy Bumppo Theatre. The protagonist was a string theorist, who used physics as an escape from the messy complications of human interaction; it was a great play, in which the physics was scientifically correct and cleverly deployed to illuminate the plot. The second play will remain nameless. Its protagonist was also a string theorist, but the moral of this story was that the best way to make a breakthrough in string theory would be to give up all those bothersome equations and hike around the mountains in India seeking enlightenment. There’s a joke in there somewhere about the Landscape, but I don’t think that’s what the author was aiming for.

So it’s worth supporting the good stuff — for example, you could do worse than starting with Lauren’s book, a collection of three of her plays. As Sir Isaac Newton says, in words Lauren put in his mouth:

Men have died chasing what I’m after! Sacrificed life and loyalty. It is not funny. This consciousness is as serious as you can possibly come close to knowing. You should treat it as such.

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Lessons from Monopoly

Sometimes the technological marvels that are the most useful are those you didn’t even know you needed. Here is a perfect example: from iFone, a version of Monopoly for your cell phone. That’s right, Parker Brothers’ classic board game, downloadable for a few bucks, so that you can match your wits against one or more computer players whenever you like. (One jarring feature of the iFone version: it’s a British company, so all the properties are named after places in London, rather than Atlantic City. Mayfair instead of Boardwalk, Trafalgar Square instead of Indiana Avenue, etc. Disconcerting.)

Monopoly guy Monopoly, of course, is famous for being that game you used to play as a kid that never quite finished, since it took forever for someone to win. The cell-phone version is no different, but it’s trivial to stop and start again much later, and the patience of the little phone CPU brain is enormously better than that of your brothers and sisters. In fact the computer players are pretty good — they are capable of making trades and all that, and they’re smart enough to value a property very differently depending on whether it will complete a full set of one color or not. But there are a few things the computer doesn’t quite understand; for example, completing a monopoly is much more valuable for a player that has enough extra cash to start building properties than for one who is completely cash-poor. And building houses is the key to actually winning the game; the computer is also reluctant to mortgage a few properties in order to build on some other ones, a classic mistake.

So overall my cell phone provides a challenging opponent, but one I can usually beat. It does my sense of self-worth good to know that I am so much smarter than a piece of high-tech equipment. And the story of my stirring come-from-behind victory while waiting in the customs queue at Heathrow will be celebrated by epic poets for generations to come (or would be had there been better documentation of the event).

But the interesting things, not having played Monopoly for years, are the moral and political implications that follow from the game. We think of Monopoly as the quintessential embodiment of laissez-faire capitalism: a competition within the unfettered free market, starting from a level playing field and allowing nature to take its course. Which is all true. But what the game really illustrates are the shortcomings of capitalism, as effectively as one could imagine; if I didn’t know better, I would think that Karl Marx himself had designed the game. Consider:

  • The game perfectly demonstrates the instability of the free market (which it should, if someone is going to “win”). That is, the rich get richer, as they can leverage their wealth to increase their earnings. Makes for a better board game than a society.
  • Talent does not win in the end. Sure, there is some judgment involved in when to make certain trades with other players, but the biggest single factor in winning or losing is a literal roll of the dice! How bleakly fatalistic can you get?
  • The playing field is initially level, but only in a completely artificial way. It’s perfectly clear that, if the game worked like the real world in which some people were born into wealth and others were not, the aforementioned benefits of being rich would absolutely dominate. Not much room for social mobility. A devastatingly effective argument for preserving the estate tax!
  • Most telling of all: your income does not come from working, it comes from collecting rents. Later in the game, when a few players have started to build houses, you quickly discover that you lose money during your own moves, and only make money during the other players’ moves.
  • It follows that, later in the game, the best square to land on is Go To Jail! From the comfort of Jail, you don’t have to worry about paying rents to anyone else, but you are free to accumulate wealth from your own properties. It’s really just a vacation resort for white-collar criminals.
  • The only mildly redistributive action that occurs in the game is the rare-but-devastating “building repairs” card that comes up occasionally in Chance and Community Chest, and which does impact the rich disproportionately. But, significantly, the money doesn’t go to other players, but to the Bank (which is the real source of evil in the whole game).
  • On the other hand, the game does make you hate the Income Tax. So there’s some mixed messages there.

So I’m thinking that there is quite a subtle subversive message in the dynamics of Monopoly, now being spread to a new generation through their handheld gadgets. Of course, one must already be of a suspcious cast of mind to read the above features as cautionary tales; if cutthroat competition is more your style, you might just think they are cool.

Nevertheless, as we have been known to fearlessly suggest improvements in the world’s classic games, I have a couple of ways to make Monopoly even better — more equitable without having the income distribution settle into some happy socialist equilibrium where incentives are balanced against economic guarantees. (Where would be the fun in that?)

  • To increase the role of skill in the game, change the dice-rolling procedure. Instead of simply rolling two dice and dealing with the consequences, players should be able to pick the number on one die, and then roll the other to calculate the number of spaces they are to move. Chance is obviously still involved, but a bit of calculation would be introduced, in weighing the relative merits of avoiding that property vs. being able to reach this other one. I certainly hope that the real world works like this at least a little bit.
  • To prevent criminals from benefiting from their crimes, allow other players to spring for the $50 fine (or 50 quid, in the British version) needed for someone to leave jail — and allow them to do so whenever its their turn, regardless of the criminal’s actual wishes. Again, a bit of skill is introduced, as the other players will have to judge whether it’s worth their money to spring someone from the pen, or whether they should hope that someone else will do so.

Sadly, I can’t implement these genius suggestions on my cell phone. And nobody actually wants to play the game in person any more. Still, it’s important to fight for a just and equitable society, even in rather imaginary contexts.

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Boltzmann’s Anthropic Brain

A recent post of Jen-Luc’s reminded me of Huw Price and his work on temporal asymmetry. The problem of the arrow of time — why is the past different from the future, or equivalently, why was the entropy in the early universe so much smaller than it could have been? — has attracted physicists’ attention (although not as much as it might have) ever since Boltzmann explained the statistical origin of entropy over a hundred years ago. It’s a deceptively easy problem to state, and correspondingly difficult to address, largely because the difference between the past and the future is so deeply ingrained in our understanding of the world that it’s too easy to beg the question by somehow assuming temporal asymmetry in one’s purported explanation thereof. Price, an Australian philosopher of science, has made a specialty of uncovering the hidden assumptions in the work of numerous cosmologists on the problem. Boltzmann himself managed to avoid such pitfalls, proposing an origin for the arrow of time that did not secretly assume any sort of temporal asymmetry. He did, however, invoke the anthropic principle — probably one of the earliest examples of the use of anthropic reasoning to help explain a purportedly-finely-tuned feature of our observable universe. But Boltzmann’s anthropic explanation for the arrow of time does not, as it turns out, actually work, and it provides an interesting cautionary tale for modern physicists who are tempted to travel down that same road.

The Second Law of Thermodynamics — the entropy of a closed system will not spontaneously decrease — was understood well before Boltzmann. But it was a phenomenological statement about the behavior of gasses, lacking a deeper interpretation in terms of the microscopic behavior of matter. That’s what Boltzmann provided. Pre-Boltzmann, entropy was thought of as a measure of the uselessness of arrangements of energy. If all of the gas in a certain box happens to be located in one half of the box, we can extract useful work from it by letting it leak into the other half — that’s low entropy. If the gas is already spread uniformly throughout the box, anything we could do to it would cost us energy — that’s high entropy. The Second Law tells us that the universe is winding down to a state of maximum uselessness.

Ludwig Boltzmann Boltzmann suggested that the entropy was really counting the number of ways we could arrange the components of a system (atoms or whatever) so that it really didn’t matter. That is, the number of different microscopic states that were macroscopically indistinguishable. (If you’re worried that “indistinguishable” is in the eye of the beholder, you have every right to be, but that’s a separate puzzle.) There are far fewer ways for the molecules of air in a box to arrange themselves exclusively on one side than there are for the molecules to spread out throughout the entire volume; the entropy is therefore much higher in the latter case than the former. With this understanding, Boltzmann was able to “derive” the Second Law in a statistical sense — roughly, there are simply far more ways to be high-entropy than to be low-entropy, so it’s no surprise that low-entropy states will spontaneously evolve into high-entropy ones, but not vice-versa. (Promoting this sensible statement into a rigorous result is a lot harder than it looks, and debates about Boltzmann’s H-theorem continue merrily to this day.)

Boltzmann’s understanding led to both a deep puzzle and an unexpected consequence. The microscopic definition explained why entropy would tend to increase, but didn’t offer any insight into why it was so low in the first place. Suddenly, a thermodynamics problem became a puzzle for cosmology: why did the early universe have such a low entropy? Over and over, physicists have proposed one or another argument for why a low-entropy initial condition is somehow “natural” at early times. Of course, the definition of “early” is “low-entropy”! That is, given a change in entropy from one end of time to the other, we would always define the direction of lower entropy to be the past, and higher entropy to be the future. (Another fascinating but separate issue — the process of “remembering” involves establishing correlations that inevitably increase the entropy, so the direction of time that we remember [and therefore label “the past”] is always the lower-entropy direction.) The real puzzle is why there is such a change — why are conditions at one end of time so dramatically different from those at the other? If we do not assume temporal asymmetry a priori, it is impossible in principle to answer this question by suggesting why a certain initial condition is “natural” — without temporal aymmetry, the same condition would be equally natural at late times. Nevertheless, very smart people make this mistake over and over, leading Price to emphasize what he calls the Double Standard Principle: any purportedly natural initial condition for the universe would be equally natural as a final condition.

The unexpected consequence of Boltzmann’s microscopic definition of entropy is that the Second Law is not iron-clad — it only holds statistically. In a box filled with uniformly-distributed air molecules, random motions will occasionally (although very rarely) bring them all to one side of the box. It is a traditional undergraduate physics problem to calculate how often this is likely to happen in a typical classroom-sized box; reasurringly, the air is likely to be nice and uniform for a period much much much longer than the age of the observable universe.

Faced with the deep puzzle of why the early universe had a low entropy, Boltzmann hit on the bright idea of taking advantage of the statistical nature of the Second Law. Instead of a box of gas, think of the whole universe. Imagine that it is in thermal equilibrium, the state in which the entropy is as large as possible. By construction the entropy can’t possibly increase, but it will tend to fluctuate, every so often diminishing just a bit and then returning to its maximum. We can even calculate how likely the fluctuations are; larger downward fluctuations of the entropy are much (exponentially) less likely than smaller ones. But eventually every kind of fluctuation will happen.

Entropy Fluctuations

You can see where this is going: maybe our universe is in the midst of a fluctuation away from its typical state of equilibrium. The low entropy of the early universe, in other words, might just be a statistical accident, the kind of thing that happens every now and then. On the diagram, we are imagining that we live either at point A or point B, in the midst of the entropy evolving between a small value and its maximum. It’s worth emphasizing that A and B are utterly indistinguishable. People living in A would call the direction to the left on the diagram “the past,” since that’s the region of lower entropy; people living at B, meanwhile, would call the direction to the right “the past.”

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Foundational Questioners Announced

Back in March we had a guest post by Anthony Aguirre about the Foundational Questions Institute, a new effort to support “research at the foundations of physics and cosmology, particularly new frontiers and innovative ideas integral to a deep understanding of reality, but unlikely to be supported by conventional funding sources.” Today the FQXi (that’s the official acronym, sorry) announced their first round of grant awardees.

It’s a very good list, and Anthony and Max Tegmark are to be congratulated for funding some very interesting science. If anything, I could see almost all of these proposals receiving money from the NSF or DOE or NASA, although perhaps it might have been more difficult. We see well-known string theorists (for example Steve Giddings, Brian Greene, Eva Silverstein), early-universe cosmologists (Richard Easther, Alex Vilenkin), late-universe astrophysicists (Fred Adams, Avi Loeb), general relativists (Justin Khoury, Ken Olum), loop-quantizers (Olaf Dreyer, Fotini Markopoulou), respectable physicists taking the opportunity to be a little more speculative than usual (Louis Crane, Janna Levin), and even some experimentalists working on the foundations of quantum mechanics (Markus Aspelmeyer, former guest-poster Paul Kwiat), as well as a bunch of others.

Nothing in there about finding God by doing theoretical physics. Which might have been a non-trivial worry, since currently the sole source of funding for FQXi is the John Templeton Foundation. The Templeton Foundation was set up “to encourage a fresh appreciation of the critical importance — for all peoples and cultures — of the moral and spiritual dimensions of life,” and in particular has worked to promote a reconciliation between science and religion. I am not a big fan of such reconciliation, in the sense that I think it is completely and woefully misguided. This has led me in the past to decline to participate in Templeton-sponsored activities, and the close connection between Templeton and FQXi was enough to dissuade me from applying for money from them myself.

Gareth Cook has written a nice article in the Boston Globe about FQXi and the grant program, in which I am quoted as saying that bringing science and religion together is a bad thing. Absolutely accurate, but the space constraints of a newspaper article make it hard to convey much subtlety. The FQXi folks have stated definitively that their own mission is certainly not to reconcile science and religion; in case of doubt, they’ve put it succinctly in their FAQ:

I’ve read that a goal of JTF [John Templeton Foundation] is to “reconcile science and religion.” Is this part of the FQXi mission?

No.

Indeed, they’ve been quite clear that the Templeton Foundation has just given them a pot of money and been otherwise hands-off, which is good news. And that they would like to get additional sources of funding. My own current worry — which is extremely mild, to be clear — is that the publicity generated by FQXi’s activities will be good for Templeton’s larger purpose, to which I am opposed.

But at the moment the focus should be on recognizing Max and Anthony and their friends for steering a substantial amount of money to some very interesting research. If they succeed at getting additional sources of funding, I may even apply myself one day!

Update: More quotes in this piece from Inside Higher Ed.

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Throwing While Black

Warren Moon always wanted to be a quarterback. He had all the physical tools, as well as tremendous leadership abilities and a fierce determination to win. Only one problem: he was black. As stupid as it may sound, not too long ago conventional wisdom held that black people couldn’t be quarterbacks — they were athletes, not thinkers.

Moon was a successful high school football player in LA, despite playing in the kind of atmosphere where you received death threats from gang members playing for the opposing team. But he couldn’t get a scholarship offer from a major college. Well, that’s not exactly right — he did get offers, but only under the condition that he switch positions to running back or defensive back. One school, Arizona State, recruited him as a quarterback, but rescinded their scholarship offer after they signed two other (white) quarterbacks.

Warren Moon Determined to play the position he wanted to play, Moon went to junior college for a year, where he personally sent game films to major programs throughout the country. He was finally offered a scholarship by the University of Washington, where the team had been plagued by racial tensions. At UW he was the target of relentless taunting from fans, and his own teammates expressed skepticism of his ability. Nevertheless, in his senior year Moon led the Huskies to their first Rose Bowl in fifteen years, where they beat Michigan in a stunning upset.

Moon was named MVP of the Rose Bowl, but when the NFL draft came around, nobody was interested. He wasn’t invited to any combines or private workouts for teams. Word was out that he refused to convert to defensive back or tight end, which were the only positions at which NFL teams would consider him. As Moon put it, “The quarterback is the face of the organization, and white owners still weren’t ready for that face to be a black man. The owners wanted somebody to take to the country club, and they weren’t ready for that to be a black man.”

Undaunted, he signed with the Edmonton Eskimos of the Canadian Football League. In six years in the CFL, he led the Eskimos to five Grey Cup championships, winning two championship-game MVP awards, and set a league record for passing yards in 1983. He was inducted into the CFL Hall of Fame in 2001.

The NFL finally caught on, and Moon was signed by the Houston Oilers in 1984. He and his family were again the subject of death threats, and his wife and children were eventually forced to watch the games from a private stadium box. After one game in 1991, on the verge of signing a new contract, he had to explain to his nine-year-old son what it meant when a fan in the stands had yelled “I can’t believe they gave that f—— n—– $14.3 million.”

Moon persevered, setting the Oilers club record for passing yards in his first year, but didn’t really come into his own until his third year in the NFL. He led the league in passing in 1990 and 1991, joining Dan Fouts and Dan Marino as the only quarterbacks to ever post consecutive 4,000-yard seasons. He went to the Pro Bowl nine times. By the time he retired in 2001, he was third all-time in NFL passing yardage behind Marino and John Elway, despite having played his first six years in the CFL. If he had played in the NFL for those six years, throwing for 2,500 yard per year (an extremely conservative estimate), he would have finished his career as the league’s all-time leading passer by a substantial margin.

Warren Moon wasn’t the first black quarterback in the NFL, but he set an example that made it enormously easier for others to follow in his footsteps. There are now several African-Americans starring at quarterback in the NFL; sufficient evidence, in the eyes of some, to say “See? Racism doesn’t exist!” Ignoring decades of history, they will tell you with a straight face that the competitive pressures of running a professional sports franchise make it impossible to be racist, since any non-racist organization will be able to scoop up all the undervalued players. (Somehow that sounds familiar.) This from the same folks who, not too long ago, argued that “the White community” was entitled to disenfranchise blacks because Whites were “the advanced race.”

Today, Warren Moon is being inducted into the Pro Football Hall of Fame, becoming the first player ever to be in both the CFL and NFL Halls — oh yes, and the first black quarterback to be inducted. Congratulations, Warren; thanks to the example you set, you won’t be alone for long.

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Recommended Novels

In the course of a long life, you’re going to get asked to recommend a good book to read. What should you say? Of course a sensible answer depends on who is asking, but we don’t know that, so let’s limit ourselves to books that tickle our own fancies. And we can assume, given the high-powered sophistication of this here blog you’re reading, that The Da Vinci Code won’t be first on your list. In fact, let’s also assume that you wouldn’t suggest Pride and Prejudice or Ulysses, as the idea is to make suggestions that your interlocutor may not actually have heard of.

So here’s my list — five novels that haven’t ascended into the literary canon (and are unlikely to do so), yet had me gasping with delight or shuddering with (a pleasant kind of) horror. My own personal cutoff for being obscure enough to count as an interesting recommendation was “less well known than Flaubert’s Parrot,” which otherwise might have made the list.

  1. The Debt to Pleasure, John Lanchester. This one is a favorite of various CV bloggers, as I recall. A wonderfully dark novel, structured loosely around a series of recipes. You won’t learn any new culinary tricks, but you’ll be drawn into the wicked plotting of Tarquin Winot as he spins his schemes with considerable savoir faire. The first book I recommend to people I think highly of.
  2. Thus Was Adonis Murdered, Sarah Caudwell. The opposite of dark, although there is a murder, and a good deal of British tax law. Caudwell has written a mystery novel populated by barristers of supernatural wit and cleverness, resulting in one of the most consistently amusing books I’ve ever read.
  3. The Wasp Factory, Iain Banks. Back to darkness. Banks is a prolific author, alternating between “straight” fiction and science fiction novels. This was his first, and it’s a masterpiece of twisted imagination. There’s a surprise ending, but the convoluted path by which you get there has a terrifying internal logic.
  4. Love in a Dead Language, Lee Siegel. No, not that Lee Siegel. This one is a professor of religion at the University of Hawaii, who has written the best postmodern-pastiche novel I’ve come across. Structured loosely as a translation of the Kama Sutra, complete with puzzles and self-reference and fourth-wall breaking. Likely to be most appreciated by academics.
  5. The Book of Revelation, Rupert Thomson. Picked up on a whim in an airport bookstore, this is a disturbing short novel about a ballet dancer who is kidnapped by a group of women and used for their sexual pleasure. The quick response is “that doesn’t sound so bad,” but the truth is that is very much is. This book is a thoughtful examination of deep issues of identity, freedom, and obsession.

I could confidently recommend any of them, with the understanding that my tastes are not exactly universal. Your mileage may vary.

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The Presence and Absence of Santa

Cornelia Dean, in today’s New York Times, has a collective review of a number of new books about the relationship between science and belief in Santa Claus. Here’s the key graf:

Of course, just as the professors of Christmas spirit cannot prove (except to themselves) that Santa Claus exists, the advocates for secular holidayism acknowledge that they cannot prove (not yet, anyway ) that Santa does not exist.

This is the crucial point that can’t be emphasized enough in discussions of the Christmas problem. These scientists, always talking about how they can “prove” this or that about the universe. But, if they’re honest, they admit that they can’t prove Santa doesn’t exist. Sure, we’ve had people up at the North Pole looking around, and they didn’t see any evidence of his workshop. But the belief in an actual physical workshop, right there on the ice and with elves and whatnot, is just a colorful remnant of an earlier, less sophisticated Christmasology. Today we understand that Santa is an ineffable spirit, who doesn’t directly intervene in the physical realm (except for Christmas eve, of course). Science and Christmas should be understood as distinct and non-overlapping realms of inquiry; they may work together, but can never come directly into opposition. And yes, there’s good evidence that many presents are actually brought out by parents rather than by Kris Kringle himself, but it seems implausible that all of them are. Santa is just a more elegant hypothesis.

Most of all: without the transcendent moral guidance that Santa provides, how will we know which children are naughty, and which are nice? Are we supposed to leave that up to individuals and communities to decide? Without Santa’s equitable system of rewards and punishments (coal), there would be no reason whatsoever for kids to behave themselves. They would just run around, tearing wings of of flies, setting schools on fire, murdering their enemies. No matter what you might think about the empirical case for and against the existence of Santa, we can all agree that the world is a better place if we believe in him.

PZ has more.

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N Bodies

This will be familiar to anyone who reads John Baez’s This Week’s Finds in Mathematical Physics, but I can’t help but show these lovely exact solutions to the gravitational N-body problem. This one is beautiful in its simplicity: twenty-one point masses moving around in a figure-8.

Figure-8 Orbit

The N-body problem is one of the most famous, and easily stated, problems in mathematical physics: find exact solutions to point masses moving under their mutual Newtonian gravitational forces (i.e. the inverse-square law). For N=2 the complete set of solutions is straightforward and has been known for a long time — each body moves in a conic section (circle, ellipse, parabola or hyperbola) around the center of mass. In fact, Kepler found the solution even before Newton came up with the problem!

But let N=3 and chaos breaks loose, quite literally. For a long time people recognized that the motion of three gravitating bodies would be a difficult problem, but there were hopes to at least characterize the kinds of solutions that might exist (even if we couldn’t write down the solutions explicitly). It became a celebrated goal for mathematical physicists, and the very amusing story behind how it was resolved is related in Peter Galison’s book Einstein’s Clocks and Poincare’s Maps. In 1885, a mathematical competition was announced in honor of the 60th birthday of King Oscar II of Sweden, and the three-body problem was one of the questions. (Feel free to muse about the likelihood of the birthday of any contemporary world leader being celebrated by mathematical competitions.) Henri Poincare was a favorite to win the prize, and he submitted an essay that demonstrated the stability of planetary motions in the three-body problem (actually the “restricted” problem, in which one test body moves in the gravitational field generated by two others). In other words, without knowing the exact solutions, we could at least be confident that the orbits wouldn’t go crazy; more technically, solutions starting with very similar initial conditions would give very similar orbits. Poincare’s work was hailed as brilliant, and he was awarded the prize.

But as his essay was being prepared for publication in Acta Mathematica, a couple of tiny problems were pointed out by Edvard Phragmen, a Swedish mathematician who was an assistant editor at the journal. …

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