Many Worlds

Stranger than fiction: parallel universes beguile science – INQUIRER.net, Philippine News for Filipinos

Is the universe — correction: “our” universe — no more than a speck of cosmic dust amid an infinite number of parallel worlds? A staple of mind-bending science fiction, the possibility of multiple universes has long intrigued hard-nosed physicists, mathematicians and cosmologists too. We may not be able — at least not yet — to prove they exist, many serious scientists say, but there are plenty of reasons to think that parallel dimensions are more than figments of eggheaded imagination.

I just finished reading His Dark Materials a few minutes ago, so it was interesting to run across this.

The many worlds hypothesis makes sense to me. And it also seems logical how, if such worlds exist, they’re separated.

Basically, it seems obvious that the vectors of parallel realities lie on a perpendicular axis of time to the one we’re aware of. Think about it: the usual framework suggests that you’ve got an infinite number of parallel universes. Some of them are very different from our own, but there are also an infinite number which are only very slightly different: one leaf on one tree in Yellowstone Park is eighteen molecules narrower, or something ridiculous that. In our universe, one of a billion billion electrons in my hand zigged; in the universe next door, it zagged.

If so, then clearly, what would differentiate these universes is that different things happen in them. The key word here is happen; we measure the course of events with time. The difference between, say, Gordon Brown’s current vector in the universe and Winston Churchill’s is very very minute, in terms of three-dimensional coordinates, since both men occupied the same house (10 Downing Street in London) and held the same job (Prime Minister of England) and therefore probably the same offices. In the first three dimensions we perceive, their positions overlap a hundred times a day.

But they are separated by decades of time, though they occupy much the same physical locality. To accurately differentiate Gordon Brown’s vector from Churchill’s, you must describe each vector in four dimensions.

So: presuming these parallel universes began almost entirely identically (which is not at all an obvious assumption), what differentiates them? Not time flow; presumably most or all came into existence at the same time, or nearly so. The universe where the electron in my hand zigged instead of zagged must be identical in age, otherwise my hand would not be there for the electron to zig or to zag. It must also, logically, be the same dimensions as this universe, otherwise my hand would not be there again; it would be somewhere else, described by some other 3-dimensional coordinate.

So if this sort of thing is true (and I’ve seen research that suggests this is a pretty good likelihood, specifically some of David Deutsch’s interesting experimentation with single-photon slit methodology) what differentiates them? Not that things do happen, and not where things happen…but rather what happens.

Which suggests the idea that each universe follows a single, directional, but different timeline. They’re all moving forward (presumably). Entropy happens in each one. It just happens in a different way.

So if you have a series of single-dimensional lines running parallel to one another, by definition, their position is identical in one dimension but different in another. Imagine laying a bunch of pencils lined up along the edge of a table. They all occupy the same position along the width axis of the table…but they’re different along the height axis. (And the depth axis, but that’s another problem entirely.)

So it seems logical to assume that the difference between the location of these universes is along a second temporal dimension, one of possibility: what happens in each universe. Same time flow, same size…just different possibilities.

It also seems obvious that, if these universes do sort of line up like soldiers, that neighboring universes would be nearly identical. If you were, for example, to stand outside of all of these worlds and start by observing our world and its direct neighbors, you’d find them almost identical. The ones on either other side would be a little more different (two electrons in my hand would zig instead of zag), the next two slightly more so, and so on, until you’ve covered every possibility (I — or the “me” in that universe — am actually a descendant of Bilbo Baggins, sitting at my table in Bag End, typing this on my little hobbit computer…or I am a sort of sentient sphere living on a massive planet with high gravity, communicating by acidic glandular secretions that etch ideogrammatic representations of my thoughts into the hard ground below me…or whatever).

Each world is simply another set of possibilities. A lot of them, of course, wouldn’t have survived past the first nanosecond of their Big Bang, and in a lot of them, life would have never taken hold at all, dead and empty universes. In others, life wouldn’t have happened yet; in still others, life would already be over.

In fact, my supposition about identical dimensions of measurement — size and time — would only really apply to the universes directly neighboring our own. Beyond a few universes down the road, you couldn’t make any guesses. (You couldn’t even necessarily guess in the universes next to ours, but it seems at least likely that they’d be at least that similar to our own.)

See, if people like Deutsch are right — if these universes do interact with one another at a quantum level — then, by definition, the particles interacting share identical physical and single-dimensional vectors. They exist at the same place and time, otherwise how could they interfere with one another? They simply share different outcomes, different possibilities, different timelines.

I don’t know why nobody else has made this assumption. It makes quantum theory a lot easier, and you only really need one extra dimension (and maybe two, if you assume that these universes are not simply spread out on a line but exist in sort of possibility clouds, in three dimensions of space) instead of twenty-two or whatever it is in string theory right now.

I mean, granted, I have only a slightly better grasp of quantum physics than most non-physicists, but it still seems like an obvious place to start from, if you’re going to try and work in this area at all.