Thursday, July 28, 2011

Doubling Down On The Multiverse

Scientific American magazine is kind of like Men's Health these days, and as seen on its August 2011 cover, SciAm's version of "Get Rock Hard Abs" is anything having to do with the multiverse. The real existence of an ensemble of very different universes, much too far away to ever be seen, has become a popular speculation. But it's nothing more than an imaginative idea invented by well-meaning humans who seek explanations without having enough information — not terribly unlike the idea of "God."

First, some background: The idea of a multiverse originated in the 1950s, when a graduate student named Hugh Everett wrote one of the most influential Ph.D. dissertations ever. He argued that just as the electron cloud surrounding an atomic nucleus represents all possible positions for that electron (were we to pin down its location), so the entire universe, obeying the same laws of physics, must have a "universal wave function" that represents all possible configurations and courses of events within the universe. The idea took root in the form of a world that is constantly splitting or branching into different possibilities; when you decided to turn right at that intersection and collided with a bicyclist, there's another "branch" of the universe in which you turned left and got a traffic ticket. We can't observe how the other branches turn out, but some physicists believe that those branches are every bit as real as the branch you and I are currently experiencing.

Over the decades, the multiverse idea has evolved; currently there are four definitions of "multiverse" under consideration. A Level I multiverse proposes simply that our universe is infinitely large, and we can observe only a tiny region. Other regions have the same laws of physics but different distributions of matter. Therefore, with an infinite number of these regions, some of them must be similar to ours — including perhaps a world where everything is the same as our world, except you turned left at that intersection. In a Level II multiverse, the laws of physics vary from place to place; only our local "neighborhood" operates on the physical laws familiar to us. A Level III multiverse is the kind originally envisioned by Everett, where there is really only one local universe, but within that universe are an infinite number of branches — including a branch where you turn left, and some branches where the laws of physics started out completely different and matter never formed. Finally, a Level IV multiverse comprises the sum of any and all possible mathematical structures that may represent universes, with the mathematical structures themselves being fundamental or irreducible entities, not the universes they represent. In a Level IV multiverse, "self-aware substructures" (which are also fundamentally mathematical) arise — conscious beings like you and me.

Granted, Level III and Level IV multiverses are abstract and subtle. Maybe that's why, in popular science media, you hear so much more about Level I and Level II. For example, in the History Channel variety of science "edutainment," the Level II multiverse, with its vast array of distant "bubble" universes, all with different physical constants, has become the default go-to explanation for why our universe appears to be fine-tuned for the existence of matter. Fine-tuning has become a problem in physics in the last couple of decades, but the Level II multiverse offers an easy way out. If there are an infinite number of bubble universes, each with different physical laws, surely some of those would have laws that support the formation of matter, and eventually life. So, finding ourselves in such a "fine-tuned universe" should not be surprising at all.

Here is where I bristle. Yes, we do need an explanation for our peculiar and benevolent set of physical constants that's better than "a loving intelligent creator designed the universe to be that way." But let's not be ridiculous about it. Proponents of the Level II multiverse insist that other bubble universes must exist for no other reason than we find ourselves living in one such bubble. To me, that's an arrogant and small-minded conclusion to draw. As I've argued previously, it's like seeing MTV playing on your television, and then based on that one observation, concluding that there must be hundreds of invisible TV cables somehow entering your home, each carrying a different channel.

In The Trouble With Physics, Lee Smolin writes that one of the greatest powers of science is to protect humans from their own imaginations. We are very good at noticing patterns in the world and generating possible explanations for those patterns. But when we aren't given enough information — as is always the case — our creative imagination fills in the gaps. Whether it's the Earth supported on the back of a turtle, or a Judeo-Christian Yahweh dividing light from the darkness, our naive explanations tend to be fanciful. Medieval astronomers imagined the Sun and planets moving on rotating crystal spheres, but then Copernicus, Galileo, and Kepler showed that the crystal spheres weren't necessary. The same happened to the aether, the invisible medium of space that was believed to carry light waves, and which was vanquished by Einstein. This steady correction of fanciful human fabrications is the legacy of science. "More than anything else," Smolin writes, "[science] is a collection of crafts and practices that, over time, have been shown to be effective in unmasking error. It is our best tool in the constant struggle to overcome our built-in tendency to fool ourselves and fool others."

So we have the bubble universes, which are posited to "really" exist, despite being completely unobservable. If science is our best hope for unmasking wrong explanations, it can't help us here. Unchallenged, the bubble universe theory could persist for hundreds of years, as untested as Judeo-Christian creation before it, simply because it is an explanation, even if it isn't a scientific one. This is why it irks me to hear an authority in physics just lay it out, as verified truth, that distant, very different bubble universes really do exist out there — that this view explains everything. No need to think about the issue anymore; it's been solved. You've just gotta have faith!

I am reminded once again of a telling moment from Carl Sagan's Cosmos. Long ago, people wondered what was on the surface of Venus. Through a telescope, the planet was a white blur. It must be covered with clouds. If it's covered with clouds, it must rain a lot, and the surface must be wet and swampy. If it's swampy, there must be swamp creatures, maybe even dinosaurs. As Sagan put it, "Observation: Can't see a thing. Conclusion: Dinosaurs." The crazy collection of unobservable bubble universes thought to be out there are today's Venus dinosaurs. In 100 years, we will laugh at the naivete and arrogance of this colorful, if incredibly small-minded, conception. Science moves on, forever banishing the errors of the human imagination. In this case, it's a sure thing.

Sunday, July 24, 2011

Change Happens. Quit Whining About It

It seems most people would like the world to stay exactly the same as it is right now.

Whenever something changes or is about to change, people come out of the woodwork to bitch about it. A few years ago, my city voted to build a cineplex and parking garage downtown. It seemed like a good idea — we had no movie theater, parking in town was always a problem, and it would bring much-needed tax dollars to the city. But immediately, lawn signs started springing up: STOP THE MEGAPLEX! Letters to the paper argued that the "gargantuan" structure would destroy the character of downtown, increase traffic and pollution, etc. People liked the town the way it was, and they wanted it to stay like that. Period.

Of course, now everyone loves our movie theater.

A recent news broadcast profiled the coming transition of the Golden Gate Bridge to an all-electronic toll system. Toll takers were told they'd be out of a job in 18 months. Naturally, they lamented the change. "It's gonna be a ghost town around here," said one of the toll takers. (Aside from the 120,000 vehicles per day, I suppose.) The same program reported that a struggling local city needed to restructure its school district, consolidating schools and closing several of them. Angry parents pleaded with the city council — it is "so sad" for schools to close after all these years, it's stressful for a child to change schools and make new friends, etc. And it seems just about every month, a local bookstore or video store falls victim to the Internet. It's all so terribly sad. ("For years, I've been going to Border's to decide what to buy on Amazon. Where will I look at books for free now?")

Yes. Change can be sad. When it happens against our wishes, we get angry. But it's inevitable, our efforts to prevent it notwithstanding. Children grow up, despite their parents' desire to "protect their innocence" for as long as possible. Marriages split up, after many miserable years of trying to make it work. Old people die, despite modern medicine's efforts to keep even the most hopeless patients alive, so that the family can put off being sad just a little bit longer.

Obviously, losing a person or anything else of real value is sad, but I don't understand this automatic connection between change and sadness or resentment. Perhaps people feel that the world around them can and should remain unchanged as they go about their life. Maybe being disabused of that idea is why people feel loss when confronted with any change at all. They bemoan "the end of an era," because that's just what you say when something changes. Gay marriage is opposed because it "redefines marriage," which is just another way of saying it's the end of an era when only certain couples could marry. People tend to stay loyal to brands, and they scream when their brands change or go away. Even the most inconsequential changes, such as changing the name of a street, are resented. ("It'll always be Cripplegook to me, dammit!")

We should fight this instinct and actively embrace change. In the long run, change usually works out for the better. You might have to put up with the road being dug up for 18 months, but when it's over there will be a new subway. You may have had to replace your VHS collection with DVDs, but how sad is it to no longer have to rewind them? We all know someone who once lost a job or relationship, yet later described it as the best thing that could have happened, for one reason or another. Even the saddest thing of all, death, has an upside. We'd never be here today if old life didn't die off and make way for new life. (Although I've gotta say, when all those dinosaurs died it was literally the end of an era....)

The next time something changes that makes you sad or resentful, ask yourself where this emotion might be coming from. It is because the world is moving on and you aren't ready for it? Is nostalgia playing a dominant role? Have you considered the upside and the long-term view? Beware of a stodgy perspective justifying your reaction. ("Well of course the hardware store closing is sad — they've known me for 40 years, dadgummit. I mean, go to Home Depot and try to find castor oil and Shinola. Crying shame, it is.")

The world is dynamic. It evolves and moves on, usually for the better, in one way or another. If you try to stand in the way of that, for no other reason than the fact that it's change, you're more of a problem than a solution.

Click on the cartoon (twice) to enlarge it.