So how does MWI deal with that? Well suppose there are two states, showing amplitudes: 0.6i |1> + 0.8 |2>. (Sometime I'll get around to improving the symbols here.) When we look we find either |1> or 2>, at respective probabilities 36% and 64%. But we started with two states, and no statistics. In WMI, neither states just "goes away" and the true outcome in the mulitverse has no preference - hence no genuine statistics of e.g. a real card game (heh, well a "real card game" as we imagine it in a classical world or collapsian world!) But there "are" only two states, even if we keep both and just somehow decouple them from each other. How oh how to get 36% of one outcome and 64% of the other? A mere split wouldn't do the trick, since I'd have equal chance of ending up in either outcome. After all, the amplitudes are just intensities, not actual sets of things. (And if they were, how many would there be in each set? Some arbitrary number? But if infinite such as Aleph null, no way to have the ratio.)
So the MWIers double-talked their way into some mystical, inexplicable sort of thickness of the wavefunction that somehow stands in for real statistics (like, authentic frequentism) that they call "measure." Everett imagined that one's "subjective probability" of ending up in a world depending on this "depth" (which BTW is not the amplitude, but its square.) We see an illustration on p. 172 of the silly and fawning book Schrödinger's Rabbits by Colin Bruce. Huh? That's just doubletalk. What the heck is that? If there's no unique self but both states |1> and |2> continue to evolve, then it isn't like the chance that one "self" will end up in world A or world B. They can't explain what they mean by that. Real quantum experiments do build up patterns the same as are generated by classical sources of unique outcomes.
Furthermore, this sort of "measure" is not the authentic probability measure in statistics. Maybe that fools readers about MWI into thinking a sort of inherent, hand-waving mystical equivalent of real probability (of how many of one v. the other) is mathematically rigorous and kosher. But I can't see any way to explicate the phony MWI "measure" and explain what's it's proponents claim is going on. For example, in Rabbits we see this quote:
"He has his own take on the question, does measure require large, maybe infinite numbers of each world-line to generate the correct probability ratios. For him, measure has no more meaning than it is postulated to have. You could perhaps (very loosely) think of it as a kind of tag attached to each world-line with a percentage value written on it, but certainly not in terms of huge stacks of each world-line."
Huh? A "tag" in which you just wave a wand and say "there aren't really more of one than the other, but it's as if there were." How?! This is an abomination, it's intellectual irresponsibility.
Another big complaint I have about MWI is about where in the chain of events, does the separation of states come about? Briefly here, I may have more later: In MWI, observation is not special. So, that juncture should not be the specific instigation of the separating of the states. Now consider a Mach-Zehnder Interferometer with photon entering and "splitting" at BS1. So shouldn't the photon state "separate" at the first beamsplitter instead of after recombining at BS2? Why not? That's supposedly a choice between taking the lower leg or the upper leg, isn't it? But if that happened, then the lower and upper paths are "separated" - so why should they be able to interfere later? Yet we know there's interference. I realize that issues of of decoherence complicate that, but it's food for thought. (I also have big gripes about the idea that decoherence explains collapse. Read more elsewhere on this blog, or Google for decoherence + "circular argument."
Schrödinger's Cat is still wanted, dead and alive. Reports of his liberation from uncertainty are greatly exaggerated. Is there an answer? I don't think so. I believe the universe is just not always amenable to our modeling hopes and capabilities. We should have the humbleness to accept that could be the case. It sure beats coming up with disingenuous "models."
*(Well, squared moduli, but the complex numbers just show relative phase. We can represent phases between real AC currents with complex numbers if we want to, it doesn't suggest anything about how "real" the currents are or not. So it's a canard to say "the WFs aren't real, because they "are represented" by complex numbers. Uh, no - not "are represented", that's just a choice. And if the WFs aren't real, what the hell is really there?)
Labels: quantum mechanics