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Many Worlds interpretation is crap

The universe, to the best of our scientific knowledge, is non-deterministic. This pisses a lot of scientists off.

The field of quantum mechanics studies many situations where particles seem to behave as if they were in two places at once, or (equivalently but a lot more weirdly) where the same event happens at two different times. Scientists can infer this behavior by observing effects like interference patterns [1], but they never actually detect the particle in both places: whenever they try to observe the particle, they only ever detect it in one place. And here's the kicker: which of the two places the particle is observed is indeterminate, there's no way to predict it. All you can do is make statistical observations (such as: it'll zig 40% of the time, and zag 60% of the time [2]).

Erwin Schrödinger tried to explain this paradox as "wave function collapse". What he suggested was that the particle is in both places at once, but when the particle is "observed" (meaning: when it directly interacts with another particle) its existence collapses into a single location. The wave function is a probability of which location it will collapse to.

However, most scientists (Schrödinger included, who gave us a tongue-in-cheek large scale consequence of that explanation) don't like not being able to predict things. Albert Einstein was perturbed by this explanation; he once said "God does not play dice with the universe".

In the years since Einstein and Schrödinger's heyday, another explanation has come into fairly wide acceptance, one that eliminates the indeterminacy (and, thus, the scientists' own sense of inadequacy). What they claim is that, yes, the particle does exist in two places at once, but when the particle is observed, the wave function doesn't collapse. Instead, the universe splits: and in one universe, the particle is observed in one location; in the other universe, the other location. This supposedly happens every single time a particle with multiple quantum states interacts. This is known as the Many Worlds interprtation.


I'll cut to the chase. Scientists should run away screaming from this explanation because what they've done is asserted the existence of universes where where God demonstratably exists, which is a no-no for any respectable scientist [3].

You see, although quantum effects are small, they do have large scale consequences. If all quantum possibilities are realized, then there is a universe somewhere where all the particles zag in such a way that their cumulative effect results in demonstratable benefits to people who pray to a certain god, and scientists in that universe measuring this effect will have to conclude that that god exists.

Not only that, but there are universes like that that will branch off this one. If Many Worlds is true, then there is a universe branching from this one where scientists will wake up to discover that a plague has appeared that attacks everyone but Christian fundamentalists. Richard Dawkins, Steven Jay Gould, and Carl Sagan will have to eat their crow in that universe. (I realize that last two have died, but they aren't dead in that universe. Although the universe we're talking about did branch off this one, various quantum effects combined in such as way so as to restore life to their bodies, and they rose from the grave, just in time to see a plague attack everyone but Christian Fundamentalists.) They can at least take solace in the fact that there's another universe out there with a plague that attacks only Christian Fundamentalists.

According to Many Worlds, universes have been branching off in the past. So it might comfort you to know that in some world out there you did ask that girl to the prom, but it probably wouldn't comfort you to know that in some other universe out there you were hit by a car and spent your whole life living as a quadriplegic.

It's also likely, accoring to Many Worlds, that you're immortal. Many theories on aging put at least part of the blame on the gradual chemical breakdown of molecules in the body. If all quantum possibilities are realized, then in some universe those chemical breakdowns will not occur, and you'd live forever, or at least until the world ends. Which sounds nice, perhaps, but that forever could be in a dungeon.


Enough silliness. I believe Many Worlds is crap, for various reasons, including some which are personal to me and can't rationally be demonstrated to others. But the Many Worlds interpretation should be rejected by science as well.

The fact is, Many Worlds is not a scientific theory or hypothesis, because it can be neither verified nor falsified (apart from falsifying quantum mechanics altogether). Whether the Many Worlds interpretation, or some other interpretation, such as the Copenhagen interpretation that Schrödinger wrote of, is "correct", has no bearing on science. Either interpretation results in the same observable predictions. Whether the wave function collapsed, or you are observing from Universe A, you are going to observe the same result.

The simple truth is, Many Worlds is a philosophical statement and not a scientific one. And philosophically it is the interpretation most opposed to science, because it asserts the existence of worlds where science is worthless. That is far, far worse than an interpretation that allows for mere indeterminacy.


Footnotes:

[1]Interference happens when two similar waves interact. If the waves line up in certain ways, they will cancel out in some places and reinforce each other in other places, and create moire patterns on much larger scales than the waves themselves. The strange thing about interference at quantum scales is that particles—which are just tiny waves—seem to interfere with themselves. For example, a single electron passing through a barrier with two closely spaced slits will show an interference pattern as if the electon had passed through both slits simultaneously.
[2]Because quantum scales are so small, most of these quantum indeterminacies are smeared out at our familiar human scales. If you know that 40% of electrons will zig, and 60% will zag, and you have 10 quadrillion electrons, you pretty much know what the large scale effect will be, even though the behavior of individual particles is random.
[3]This is sarcasm, or would be if it weren't more or less believed by most scientists, despite what they may say.
Tags: indeterminacy, many_worlds, quantum_mechanics, science
Permalink: http://blog.aerojockey.com/post/manyworlds
Last Edited: 6 November 2010, 11:27 PM
2 comments:
jonimethfan wrote: Many Worlds clearly sucks because it requires a single quantum event to be exothermic enough to 'create' a whole new universe like our own. I understand that wave functions experience all possible actualities continuously, but that the cardinality of those possibilities is not even countably infinite and that consequently the possible energy release is likely to be small and finite rather than cosmically enormous.
jonimethfan wrote: In any 'Many Worlds' infiniverse, Each universe would consist of a single quantum event (Think it through!) This is contradicted by the macroscopic reality of human consciousness. To paraphrase Descartes: 'I think therefore 'Many Worlds' is bullshit'.
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