Monday, January 31, 2011

The Deep Laws of the Cosmos, or Hope Springs Eternal

After my disappointment with a recent read on multiple universes and M-theory, I was hopeful that Brian Greene's latest offering, The Hidden Reality, would soothe the ruffled feathers. Thankfully, I wasn't disappointed (how can you be with statements like "gravity is matter's sugar daddy"?).

Greene has a way about him that is at once knowledgeable and endearing; he starts his description of parallel universes with a story from his childhood. It isn't forced or unnatural. He wants you to understand.

Though Greene has substantially more space to take tangents (141 more pages than Hawking, though I can't attest to the font sizes or line spacing being the same...), he stays on topic. No random digressions into Newton's church attendance or arguments against philosophy or religion (he does tell some funny side-stories, including one about Gamow's notorious sense of humor, but they are all couched in the point at hand: he introduces a person before introducing that person's key insight into the scientific theory being described), no vehement arguments over free will or aversion to individual scientists due to their beliefs (in fact, Greene even describes some groundbreaking work by Weinberg, among others, who used as his motivation the so-called "anthropic principle"). Greene uses amusing anecdotes, relevant references to popular culture (Cartman makes what may be his scientific debut), and his own insight from years of personal experience to describe what would otherwise be completely inaccessible to anyone without a graduate degree in mean field theory. And despite being more in-depth than the recent Hawking publication, he doesn't mince words or add fluff. There's nothing wasted in that extra volume.

Nine versions of possible multiverses (multiple/parallel universes) are presented, each with appropriate historical and scientific background, as well as - gasp! - possible scientific experiments which could test for each of them (not much can be done with the current level of technology, but the future is bright and the possibilities copious). In Greene's terminology, they are: the Quilted Multiverse, Inflationary Multiverse, Brane Multiverse, Cyclic Multiverse, Landscape Multiverse, Quantum Multiverse, Holographic Multiverse, Simulated Multiverse and Ultimate Multiverse (parts a and b). Briefly - and really, you should read the book - they can be explained as follows:
  1. Quilted Multiverse: if the universe is infinite (in space), conditions will necessarily repeat across space, which yields an infinite number of parallel worlds. We wouldn't "see" these parallel universes-within-the-universe, because they'd fall outside of our cosmic horizon (the distance limit we're able to observe due to the finite speed of light). This multiverse proposal arises mainly from general relativity, which doesn't require that the universe be finite.
  2. Inflationary (or Bubble) Multiverse: with the advent of inflationary theory, with its "inflaton" field (it can essentially be thought of as an antigravity field), to describe the beginnings of our own universe, an interesting tangent arose. The inflaton field could yield different areas of inflation (due to quantum fluctuations; this is how Cartman got involved, believe it or not), each forming a "bubble" within which a universe would form.
  3. Brane Multiverse: our first true string theory contender, "branes" are higher-dimensional objects within the string theory framework. A universe like ours could exist on a three-dimensional brane (for reasons he explains, the universe is essentially "trapped" on the brane), but more branes could exist elsewhere in the multi-dimensional space which carried their own universes.
  4. Cyclic Multiverse: the "braneworlds" from the Brane Multiverse, since they can move, have the potential to collide within the larger-dimensional space. If and when they do, the universes on each are completely annihilated and begin anew. Since branes are gravitationally attracted like any massive object, they could be pulled in and collide over and over, creating many new universes.
  5. Landscape Multiverse: delving deeper into string theory and adding in inflationary theory, we find that the multiple dimensions allowed by string theory subsequently allow an entire N-dimensional "landscape" upon which an infinite number of inflationary bubble universes could form.
  6. Quantum Multiverse: this may be the most familiar of the list. It refers to the Many Worlds interpretation of quantum mechanics, which flew in the face of the historical Copenhagen interpretation. In essence, each quantum possibility (is the electron here or there?) is actually manifested in a parallel universe (in our universe, it's here, but simultaneously in a parallel universe, it's there).
  7. Holographic Multiverse: strange, cutting edge science from string theory, quantum field theory and black holes suggests that our universe may just be a mirrored or projected "image" from a distant, differently-dimensioned (2D instead of 3D?) but physically equivalent parallel universe.
  8. Simulated Multiverse: the most banal but perhaps most immediately relevant, technological growth may make it possible for entire, self-consistent, self-aware and self-propagating simulated universes to be created.
  9. Ultimate Multiverse: Part (a), if you will, is actually philosophical - the "principle of fecundity" asserts that every possible universe is a real universe (even the ones made entirely of gorgonzola or the ones made of nothing), thereby nullifying the question of why our particular universe is the one which exists. Part (b) trims this slightly by introducing a level of self-consistency, proposing that every possible mathematically consistent universe is a universe, or, more correctly, that "these universes instantiate all possible mathematical equations."
What struck me most of all, however, wasn't Greene's incredible ability to explain string theory (I almost found myself believing it... don't tell my string theorist friends!), or his encyclopedic knowledge, but his belief in the future of science. Completely contrary to the conclusions drawn by Hawking and Mlodinow in their text, which amount to "we have a bunch of piecemeal theories which describe our universe, but our universe is only one of many, and therefore we can't achieve some beautiful mathematical description of the universe and our piecemeal theories are the best we're going to do," Greene candidly admits that not only does he believe we may still discover a true Grand Unified Theory, he hopes we will.
"The breadth of multiverse proposals... might suggest a panorama of hidden realities [essentially, what Hawking/Mlodinow were suggesting]. But I've titled this book in the singular [The Hidden Reality] to reflect the unique and uniquely powerful theme that underlies them all: the capacity of mathematics to reveal secreted truths about the workings of the world. Centuries of discovery have made this abundantly evident; monumental upheavals in physics have emerged time and again from vigorously following mathematics' lead.... [The] multiverse proposals similarly rely on a belief that mathematics is tightly stitched into the fabric of reality."
However, he continues:
"Our universe is not the only one possible [if these theories are true]. Its properties could have been different.... In turn, seeking a fundamental explanation for why certain things are the way they are would be pointless....
I don't know if this is how things will turn out. No one does. But it's only through fearless engagement that we can learn our own limits. It's only through the rational pursuit of theories, even those that whisk us into strange and unfamiliar domains, that we stand a chance of revealing the expanse of reality."
Lastly, on a bit of a schadenfreude note, I wished to make a point about philosophy. Unlike Hawking and Mlodinow, who seem to believe that philosophy is dead, Greene takes a far more reasonable standpoint. During a philosophy course as a freshman at Harvard, he was challenged by his professor: "Let's say you find the unified theory," he said. "Would that really provide the answers you're looking for?" The answer is, of course, no. The philosophy professor was right, and Greene knew it. It was this encounter which prompted Greene to consider the concept of the Ultimate Multiverse - proving, it would seem, that instead of philosophy being dead, it is alive and well and helping to push forward the frontiers of science.

And one last poke, at those Dawkins-ites:
"I understand well the impulse to tether scientific investigations to those propositions that can be tested now, or in the near future; this is, after all, how we built the scientific edifice. But I find it parochial to bound our thinking by the arbitrary limits imposed by where we are, when we are, and who we are. Reality transcends these limits, so it's to be expected that sooner or later the search for deep truths will too.... Sometimes [science] challenges us to reexamine our views of science itself."

Fail

I intended to write a post on Brian Greene's new book, The Hidden Reality, which I finished last night and which came out a few days ago. But the best intentions are often thwarted by... weather.
It took me almost an hour to get to work this morning. Snowy roads and idiots in four-wheel-slide SUVs kept the pace at half normal. But this evening... this evening was far, far worse. Snow and ice was only a part of it. Traffic was horrendous. It was so cold outside that my car's heating struggled to keep above the peg at the bottom of the dial. It was nearly three hours after leaving my office that I finally made it home. I know some people are used to commuting. I'm not one of those people.
There are generally three stages which one goes through upon encountering traffic.
Stage 1: Optimism. It doesn't look too bad from here, you think. I can get through this without too much hassle. It won't last long. Perhaps you even turn the radio up a bit too loud and sing along with AC/DC, much to the chagrin of those trapped in cars around you.
Stage 2: Anger. The optimism from Stage 1 quickly drains, replaced even more quickly with frustration. It's not fun anymore, and soon it's positively embolism-inducing. You grumble, shout, gesture, hit the steering wheel, honk the horn, drive so aggressively that your fuel economy is quartered. More often than not, the commute, or at least the traffic, finally ends during this stage. We slam the door as we come in, breaking a picture frame by knocking it off the wall, then drop into a vague remorse and soothe ourselves with a beer.
Stage 3: Catatonic. It's not often one reaches this stage, but after two hours of strain on your shifting knee, the possibility arises. You're resigned to your fate. There's nothing left in your future but more traffic. Taillights as far as the eye can see. You're no longer really there, no longer fully present inside your own head. Your eyes don't waiver from straight ahead, nor is any movement anything more than an automated gas-brake-gas-brake. You're dead inside. The traffic wins.
Needless to say, I hate commuting. I may work from home tomorrow. Maybe then I'll be able to tell you about Brian Greene.

Wednesday, January 19, 2011

The Grand Design, or Why I Hate Reading Books About Science

When you set out to write a popular science book, as Stephen Hawking had presumably done in the recent "The Grand Design" (coauthored with Caltech physicist Leonard Mlodinow), you generally should discuss... well... science.

When you've already made the statement "philosophy is dead" in the first two paragraphs of the book, you're not doing yourself any favors.

When on the first page you introduce the ancient Greek/early Church version of science as "the traditional conception of the universe," I'm bound to start losing my patience.

When you spend the next 80 pages bashing Aristotle for not knowing the scientific method (it hadn't been invented yet) and Newton for being a deist (a lot of science wouldn't have been done had the scientists themselves not believed in a God who set the laws of the universe in motion that we might even be able to measure them), dismissing myths and fables as feeble, uncivilized attempts at pseudo-scientific explanation (everyone knows fairytales are meant to teach, not to explain), and extolling the idea that "free will" is only a result of our inability to do the complicated calculations necessary* (sorry, guys, but scientific determinism went out the window with quantum mechanics), then you're lucky I have enough tenacity to finish reading.

This is, I'm afraid, the bane of modern science. Scientists don't talk about science anymore. Hundreds of people would pack lecture halls to listen to Feynman talk about QED, but now we brush him off with a mention of that crazy "Dick" Feynman and his psychadelic Feynman-diagram covered VW bus. We instead choose, like Dawkins and the rest, to use the grand name of Science to bludgeon honest philosophic inquiry. The point of science, the beating heart of science, is not to ridicule people into agreeing with atheism! The point of science is to discover truth, and they're mainly "local" truths, and they're often only empirical parameterizations of that truth. But we don't like to talk about science, apparently. We'd rather talk about why God can't be an old white guy in a robe.
With every new "science" book I read, I find we drift farther and farther away from what we should be doing: talking about science. I want people to know how fascinating science can be, how interesting, how wonderful, how beautiful. I want to show them how we can work things out, how sometimes nature seems simple and elegant and sometimes filthy and complicated, how we can use science not only to increase our knowledge but to better our lives. I want to make scientists. But the "ivory tower" zeitgeist seems to want to make minions to science instead.
The authors finally did get around to talking about science (in their case, M-theory and the idea of an infinite number of "histories" for the universe), and when they did, it was engaging, interesting, and fun to read. But they lost it all again in the last chapter, revisiting their earlier derisions, neglecting all else. The "grand design" will be found in M-theory, they state. "Spontaneous creation" is why the universe exists, and why we don't need a god to get it started for us. But how is their "spontaneous creation" any different, in the end, from a religious "spontaneous creation"? "Because it had to" and "Because God did it" are really the same thing.

*
"It is hard to imagine how free will can operate if our behavior is determined by physical law, so it seems that we are no more than biological machines and that free will is just an illusion.... [I]t also seems reasonable to conclude that the outcome is determined in such a complicated way and with so many variables as to make it impossible in practice to predict. For that one would need a knowledge of the initial state of each of the thousand trillion trillion molecules in the human body and to solve something like that number of equations.... Because it is so impractical to use the underlying physical laws to predict human behavior, we adopt what is called an effective theory.... In the case of people... we use the effective theory that people have free will."
Quantum mechanics indicates that while we can predict the most probable outcome of any given set of initial conditions, we can't know exactly which outcome will happen. The authors even discuss this point later in the text. So even if we could do all of the trillions of calculations necessary to "predict" someone's behavior, we still couldn't know it exactly - we could only know the probabilities that they would do one thing over another. And that's not the same as determinism. So their argument that free will is an illusion... is an illusion.

Thursday, January 6, 2011

A global human history

I just finished reading Steven Mithen's After the Ice (sorry, out of print), and while I enjoyed learning a multitude of things I never knew about the prehistory of humanity (did you know pottery developed independently in Japan thousands of years before it appeared anywhere else?), what caught my eye was the concluding paragraphs:
So what about the 'blessings of civilisation'? Are the delights of the microscope, the thoughts of Darwin, the poetry of Shakespeare and the advances of medical science, sufficient recompense for the environmental degradation, social conflict and human suffering that ultimately derive from the origin of farming 10,000 years ago? Would it have been better if we had remained as Stone Age hunter-gatherers forsaking the development of literature and science? The answer is in our hands; it depends upon what we choose to do during the next hundred years of global warming - our future, that of planet earth, remains within our control.
He concludes by quoting John Lubbock, Victorian polymath and archaeologist:
Even in our own time we may hope to see some improvement, but the unselfish mind will find its highest gratification in the belief that, whatever may be the case with ourselves, our descendants will understand many things which are hidden from us now, will better appreciate the beautiful world in which we live, avoid much of the suffering to which we are subject, enjoy many blessings of which we are not yet worthy, and escape many of those temptations which we deplore, but cannot wholly resist.

Monday, January 3, 2011

Safety

So I woke this morning with that familiar sinking feeling in the pit of my stomach. Four hours each way of flights for a day and a half of "networking" hardly seems worth it, even without considering my specific (phobic) reaction.
It's been big news this holiday season, the new TSA full-body scanners... but it doesn't matter. What people fail to realize is that none of it matters in the least. In any arms race, one team must always be one step behind the other.
First, it was guns and knives, so we instituted the metal detectors. Then plastic explosives worn under the clothes, so we have full-body scanners and "puffers" (the trace element detectors that use mass spectrometry to identify chemicals that have been blown from your person into the detector with puffs of air). But what's next? There is no end to it, and anyone who stops to think about it will see that.
The scanners and puffers are useless against explosives carried internally (and let's face it, if somebody really wants to blow up a plane, then swallowing a chunk of C4 is not out of the question), and no detection method can stop something taking place outside of the secure area (think of O'Hare - the doors to the passenger drop-off lane are literally 50 feet from security lines, with dozens of people in them). Additionally, there's always a way to sneak something past security using any number of loopholes. Consider, for instance, that not all of the air cargo is scanned before being loaded onto the same plane that you've just boarded (though new rules make it required). What of the tons of products that are brought into the airport each day by the restaurants, booksellers and vendors? One bottle of Coke out of a pallet could be filled with explosives, just waiting for the person who knows to buy it from the machine. And all of this neglects the "easy" stuff, the mistakes and errors and judgment calls and weather and engineering failures that give rise to many more air accidents than terrorism.
My point is not to give people ideas (as the joke goes, sexual harassment training is the best place to learn new sexual harassment techniques), but to say simply that nothing is safe. That's just the way it is. That's life. Flying's not safe, driving's not safe, the train isn't safe and even staying at home isn't safe. The level of danger is, of course, relative; statistically, you're more likely to be in a car accident than a plane crash, or to slip in the shower than be struck by lightening. But the basic truth of the universe is that nothing is certain. Nothing.