Down at the Particle Pub

October 21, 2009

There's nothing quite like taking science to the people in the form of their local pub, particularly if it's part of the ongoing Quantum to Cosmos Festival, hosted by the Perimeter Institute in Waterloo, Canada. Last night I joined physicists Lee Smolin (a founding member of Perimeter, Jazz Whisperer, and author of The Trouble of Physics, among other books) and Cliff Burgess (McMaster University and All-Around Mensch) to chat with our fellow imbibers about the Large Hadron Collider, the Standard Model of particle physics, what one might do with an old, outdated accelerator, and after the alcohol took effect, we even delved a bit into quantum gravity (Lee's bailiwick). Good times! 

The festivities were hosted by ringmaster Wilson da Silva, Awesome Dude -- also editor of Cosmos magazine. Those Aussies know how to bring science where it counts. There are photographs of the event, oh yes, and there was supposed to be a podcast suitable for downloading, but apparently we didn't speak loudly enough and there were "technical issues" as a result. No matter. A good time was had by all, especially the panelists.

The evening's title was "The Biggest Gamble in Physics?" because Wilson believes in bringing the controversy right out of the gate. The Large Hadron Collider is a huge machine, very powerful, very expensive -- is it worth the price tag for whatever we're likely to discover (if anything)? Cliff quickly established himself as the optimist among us, convinced we will not only find the Higgs boson when the LHC (finally) turns on, but a few other exciting things too. He's expecting surprises, and looking forward to them.

I conceded that it might be difficult for the average Person on the Street to justify spending that kind of money on a big machine to explore the Big Bang when people are losing their jobs and homes in droves (especially in the US), but pointed out that there are economic benefits as well: the LHC generates jobs and spinoff technologies, many of which we can't even envision yet. And Lee brought some much-needed perspective by quoting Eric Weinstein: "For the cost of bailing out one bank, we put a man on the moon." (And that's not counting all the hefty bonuses announced this past week.)

We also commiserated about the difficulty in summing up the Standard Model of particle physics for a general audience. Wilson claims he once tried to write a short sidebar summary for a Cosmos feature, "and 748 words later, I was finally finished." I marvel he could do so in under 1000 words. I like to use the analogy of a big noisy family of particles, akin to the loud Greek relatives in the film My Big Fat Greek Wedding: there are all kinds of cousins, second cousins, aunts and uncles, half of whom are named Nick, and even the occasional crazy grandparent making a rare appearance. It's tough to keep them all straight. So with the Standard Model. Lee says his goal is to reduce the model down to something more manageable, along the lines of Goldilocks and the Three Bears. It would be easier to just have a Papa Bear, Mama Bear and Baby Bear.

That complexity, of course, is why it proved so difficult to dispel the myth that the LHC will create a big black hole that will destroy the world. No major media outlet could resist the temptation to play the Doomsday card, although the Daily Show gets kudos for ridiculing the mastermind behind the hysteria. I argued that, as annoying as the media coverage became, the LHC was the third biggest news story of 2008. The LHC has fantastic name recognition, even if it's as a Doomsday Machine.

Afterwards, we repaired to Perimeter's famed Black Hole Bistro -- it seemed fitting, if the LHC is going to make a black hole to destroy the world -- where we hobnobbed with fellow panelists, and I got to hover shyly near author Neal Stephenson (Anathem, The Baroque Cycle, and my favorite, Snow Crash) as he chatted with MIT's Neil Gershenfeld and others. Even I have my Fangrrl moments. All in all, it was an amazing festival experience, and I'm sorry I could only take in such a small part of it.

When the Multiverse Collides

September 28, 2009

The season premiere of The Family Guy was even edgier than usual, exploring numerous alternate universes in an episode entitled "Road to the Multiverse." Resident genius toddler Stewie invents a device that enables him to travel between parallel universes with the family dog, Brian -- who tries to pretend he knows about Many Worlds as Stewie explains the concept. It's a nice brief summary of the basic concept.

Soon Stewie and Brian are popping in and out of alternate universes: one that is far more technologically advanced than ours; one where everyone has two heads; one that is based on ironic Washington Post political cartoons; one that is completely Disneyfied, with cheery songs about pie and a touch of anti-semitism; and finally, a universe where dogs rule the world and humans are the pets. That's where Stewie meets his Dog Self and discovers he's had the device on "shuffle" all along -- hence their random jumping around. Eventually they manage to get back to their reality, bringing Alternate Pet-Brian back with them -- who [SPOILER ALERT!] is promptly hit by a bus, because after all, can two Brians co-exist in the same universe?

Scientists don't really know what would happen in such an instance. One of the critical features of most multiverse theories is that the various parallel worlds never interact. In fact, there's no direct evidence for the existence of a multiverse -- and only a few proposals for how one might detect them if they did. For instance, we might see evidence of another bubble universe if it had collided with our own a long, long time ago -- except such a collision would pretty much destroy the fabric of spacetime in both bubbles.

The latest scheme for evidence of a multiverse comes a new paper on the arXiv by Anthony Aguirre of the University of California, Santa Cruz, and Matthew Johnson, a postdoc at Caltech. They think they've come up with a version wherein spacetime in two alternative universes could be preserved, assuming they didn't so much as collide, as sideswipe -- a sort of "cosmic scrape." Signs of a such a scrape would include a negative curvature to the universe, or the remnant patterns that could be observed in the cosmic microwave background. The latter has the advantage of possibly being detected from advanced telescopes. Even then, it would be a sliver of evidence, not definitive proof.

It's still tantalizing stuff. Maybe cosmologists in a technologically advanced parallel universe will beat us to it, and detect our presence first -- inspired by their version of The Family Guy. Because if there's a mutliverse, there's got to be a version of Seth MacFarlane out there somewhere out there, too.

Warped Opera

August 24, 2009

Science inspires art in all kinds of surprising ways. An article in SEED last week focused on a new opera by Spanish composer Hector Parra, that debuted earlier this year in Paris: Hypermusic Prologue. The work was inspired by theoretical physicist Lisa Randall's popular science book, Warped Passages. The son of a physicist, Parra read the book and became fascinated by Randall's description of how hidden dimensions might explain why, for example, the gravitational force seems so much weaker than the other fundamental forces. And he approached her about writing a libretto for his new opera.

Parra's opera is decidedly modern, with an experimental score, as befitting such cutting-edge physics theories. There are only two roles and minimalist, abstract stage design by artist Matthew Ritchie -- apparently he makes sculptures inspired by inflationary universe theory, so Hypermusic Prologue was a natural fit for his talents.

Randall's book describes her seminal work with fellow physicist Raman Sundrum on model-building -- developing testable mini-theories of higher dimensions in the universe, rather than shooting for a full-fledged Theory of Everything, as with conventional string theory (as if string theory could ever be described as fully conventional).

String theory imagines extra dimensions -- beyond the three spatial and one temporal dimension that make up the observable fabric of space-time -- that are large, perhaps even the size of a universe, rather than tiny curled up extra dimensions the smallest possible Planck scale? Randall and Sundrum propose a model in which our universe is the usual four-dimensional brane (short for "membranes," and in this context describing surfaces that exist in higher dimensional space). The twist: that brane exists on the surface of a five-dimensional space. Gravity is the only force that is not limited to the four-dimensional brane-world. It can seep into the higher dimension(s) as well, thus making it seem weaker than the other forces.

These are heady concepts, and they make for a heady opera. Randall's libretto employs the notion of extra dimensions as a metaphor for "another view" that is "hidden yet true." Parra's score, meanwhile, uses sounds and instruments to evoke warped spacetime and changes in energy, mass, time and gravity. Per the SEED article:

"As the soprano approaches a gravitationally strong part of the universe, for example, her voice is electronically treated to make her phrases shorter in mathematically precise increments and the orchestra matches this shorter phrasing. As she enters a hidden fifth dimension, her voice gets louder and the music gets sonically richer, while Bobby's [the baritone, James Bobby's] voice -- stuck in the lower-dimensional universe -- remains digitally untreated and becomes softer and thinner."

Barcelona will host a run of Hypermusic Prologue, and from there it will tour Luxembourg and Brussels. Look for a special adaptation to come to New York's Guggenheim Museum in January.

The Pros and Cons of Many Worlds

August 20, 2009

Don't you just love a good scientific debate on cutting-edge physics theories? Yeah, me too. So I was pleased when Physics and Cake linked to this terrific BloggingHeads TV diavlog between physicist/bloggers Scott Aaronson (MIT; his blog is Shtetl-Optimized) and Eliezer Yudkowsky of the Singularity Institute and the blog Less Wrong. Among the topics under discussion: the Many Worlds theory of the universe. Eliezer is pro, Scott is mostly con -- as in, he thinks the theory is ridiculous while acknowledging it might still be right. A clip giving the "Pro" side is below. Head on over toe BloggingHeads.tv for the full diavlog and/or Scott's response. Enjoy!

No Fate But What We Make?

June 07, 2009

Terminator: Salvation, the fourth film in the hugely successful franchise, opened pretty strong a few weeks ago at the box office, but faced some criticism for abandoning the time travel underpinnings of its earlier installments, and focusing instead on a futuristic war with the machines. If you look at the progression of themes in the franchise, however, it's clear this was a natural choice for the filmmakers to follow.

In the original, of course, Ah-nold is the bad guy, a robot killing machine machine who travels back in time to take out the mother of the future leader of the resistance -- before she has a chance to meet the father of her child. The robot fails; the future is secure. Terminator 2, easily one of the best sequels in cinematic history, took the point one step further, with a toughened-up Sarah Connor trying to stop Armageddon and making this her mantra: "No fate but what we make." That is, the future isn't written in stone; if we can change the course of events. And she succeeds -- temporarily. 

In Terminator 3, we get another interesting twist. Despite all these attempts to rewrite history, the apocalypse still happens in the end -- just not in quite the same way it was supposed to happen. The implication? The future is inevitable, no matter how much one tries to change it. So the focus in T4 shifts to that inevitable future, choosing instead to ruminate on a new question: what makes us human.

Certain physicists like to nerd-gas about violations of physics in time travel movies. My own spouse, Sean, recently posted some helpful "Rules for Time Travelers" over at Cosmic Variance, outlining his pet peeves about how the topic is often portrayed in film. Three in particular are worth singling out because they relate to characters wanting to travel back in time in order to change the past.

The problem with this, as Sean points out, is that "If something happened, it happened." Based on everything we know thus far about relativity, quantum mechanics, and the like, even if one could travel backwards in time -- and this is a very difficult feat to accomplish -- it would not be possible to change the past, because the past already happened. For much the same reason, you can't travel back in time to a point where your spiffy time machine hasn't been invented yet. This is known in hip physics circles as the "chronology protection conjecture."

But then Sean comes through for sci-fi fans and includes a loophole: you can't change the past unless you go to a parallel universe. I've written about the "Many Worlds" theory before, and these days the notion of a multiverse is no longer grounds for automatic dismissal as a crackpot by the physics community.

Here's the gist: If you travel to a parallel universe, you can change your past, or at least experience a different outcome, because what you're actually doing is traveling to a different branch of the wavefunction. It's not really "your" past; you can only experience one branch of reality at a time. But things may have turned out differently for you in a parallel universe. And thus launched a thousand new sci-fi subplots.

That's certainly the approach taken on Fringe during its season finale: [SPOILER ALERT!]  Olivia starts dimension-hopping as a result of all that messing with her brain and taking some sort of weird (and totally fictional) mind-control drug called cortexifan as a kid. So she's shunting back and forth between her reality and an alternate Earth where Boston is a bombed-out ruin and the inhabitants are preparing to go to war with the "other" Earth. Or something. Also? Main character Olivia's phone is black in one dimension, red in the other, and her co-worker's desk has been moved. ZOMG! Alert the media! As io9 snarkily concludes, "So things are more dangerous and stylish in Parallel Earth."

Who knows what those crazy kids behind the wackiness that is Fringe will come up with next? Now that they've found a semi-plausible means of side-stepping the chronology protection conjecture, Olivia is free to make her own fate -- or rather, to choose the branch of the wavefunction with the best outcome, from her perspective. I hope it's one where Walter Bishop remains his zany, brilliantly wacky self, since an alternative in which he's a buttoned-down, respectable member of the scientific establishment would be too, too dreary....

Image: I Can Haz Cheezburger.

The World is Flat

January 26, 2009

In 1884, a humble English schoolteacher named Edwin Abbott Abbott published a modest little novella called Flatland: A Romance of Many Dimensions and inadvertently brought the concept of extra geometric dimensions out of the Ivory Tower and into the mainstream. Isaac Asimov once described the book as "The best introduction one can find into the manner of perceiving dimensions," and many a physicist and mathematician will tell you the tome is among their favorites. I first read it just out of college, and was immediately charmed.

Part science fiction, part satire (and a pointed commentary on Victorian social hierarchy and the Establishment's animosity towards revolutionary new ideas), Flatland takes place in a two-dimensional world inhabited by 2D circles, squares, rectangles and a variety of polygons. Our narrator is a nameless Square who dreams about a one-dimensional world (Lineland) where nobody believes that anything lies beyond their simple linear existence -- certainly not an entire world in two dimensions.

But then the little Square meets a three-dimensional Sphere, who tells him about Spaceland, existing just beyond the ken of Flatland's inhabitants. Seeing is believing, so the Sphere takes the little Square on a tour of Spaceland, literally broadening his horizons. Once back home, the Square tries to tell others about this brave new world, and is denounced and eventually imprisoned for his trouble. (There's also a dream sequence involving Pointland, inhabited by a single point who thinks the Square's attempts to talk to him are just his own thoughts -- solipsism personified.)

There have been several attempts to adapt the book to film, most recently via the animated short, Flatland: The Movie, featuring the voices of Martin Sheen, Kristen Bell, Michael York, and Tony Hale:

Flatland is not a Utopian society (it's awfully repressive intellectually, for starters), and all men (and women) are not created equal. Men are polygons, and the number of sides they have determines their social class -- triangles are the lowest of the low, while a circle is considered a perfect shape. Women are relegated to being comprised solely of lines. And since a line moving towards an observer invariably appears to be merely a point, women are required by law to sway back and forth so that the men can see them coming. Apparently there were some "accidents" where men in Flatland were stabbed to death by oncoming women. (Right. An "accident." Ahem. I'm just saying that maybe one of the bastards had it coming.)

Anyway, extra dimensions became all the rage, well into the 20th century, where the notion of a fourth (or more) dimension influenced major artists like Pablo Picasso and Salvador Dali. In fact, Dali's famous painting, "Crucifixion," depicts Christ nailed onto a four-dimensional hypercube as a cross; Dali subtitled the work "Corpus Hydrocubus."

Post-Einstein and his concept of a unified spacetime, of course, time is considered the fourth dimension, so when scientists in the early 20th century began contemplating extra dimensions, they spoke of the "fifth dimension" -- and beyond. But just as the 2D shapes in Flatland couldn't see Spaceland, we can't perceive the fifth dimension. Mathematicians and physicists wanted a solution to the conundrum, and a Swedish mathematician named Oskar Klein obliged in the 1920s by arguing that the fifth dimension could be so tiny -- curled up, or "compactified," into a tiny ball smaller than the Planck length -- that noy even atoms could pass into it.

Such so-called "Kaluza-Klein models" languished for a bit after that, until the 1970s, when string theorists adapted this extra-dimensional approach to unify all four fundamental forces (gravity, electromagnetism, strong and weak nuclear force) into a giant Theory of Everything. To get all those pieces to fit together in string theory requires a whopping nine dimensions of space and one dimension of time (ten spatial dimensions if we're talking about "M" theory). The extra dimensions are supposed to be "compactified," which is why we can't experience them directly.

So how do we know they're there? Well, we don't, any more than Abbott's plucky little Square knew Spaceland existed until he visited it. We have some very pretty math buttressing the argument, and while it's a long shot, it's possible that experiments at the Large Hadron Collider could provide evidence of extra dimensions. Seeing is still believing.

String theorists, fortunately, do not inhabit a repressive, willfully ignorant world like Flatland. They might take some heat from their more skeptical colleagues now and then, and in the last couple of years there's been a bit of a backlash. But their story has a happier ending than Abbot's little Square. They are free to openly explore radical new ideas, inspiring art, literature, theater and such in turn. Whether string theory turns out to be right, or is eventually replaced by a better model, the world is a richer place for it.

Photo: "Crucifixion (Corpus Hydrocubus)," Salvador Dali, 1954.