Recent content by toho

Looking around a little, I see that 4 follows directly from http://www.iumj.indiana.edu/IUMJ/FULLTEXT/1957/6/56050" without any additional assumptions (and without any t-inf limit assumptions). Since 1 and 2 follow directly from MWI, i guess that leaves 3 open to debate...

You misunderstand me. The way out would be to postulate a theory with an enourmous number of free parameters, curve fit to produce observed phenomena. I don't think your view of the MWI is such.

No, I am a physicist. Same school as Tegmark actually. Like so many other physicists I work with financial modelling. That is probably why I have strong opinions about uncertainty and the nature of probabilities. I am exposed to a lot of uncertainty in a very fundamental sense every day. I don't...

In the house analogy the probability measure is not unique. I think that was your point also. I argue that in MWI it is. Btw, I hope you didn't take my "nature of uncertainty" post as an insult - it surely wasn't meant that way. I like this discussion as it is intellectually challenging, and...

But the notion of probability only has meaning as a limit behavior - that is true in any application of probability theory, not just QM. Saying that a probability emerges now does not make any sense, if you don't somehow consider the limit behavior of infinitely many trials. Anyway, we were...

Yes, it does. I believe that I have done so, in the sense that it can be proven to be true (again, provided my conjecture or something similar holds). I get the feeling that what you really are after is a some kind of explanation of the nature of uncertainty. I cannot provide that. What I can...

I understand, but your argument (that I can't remove the t->inf limit in the conjecture by dividing up the Hilbert space of the wave function into a countable sequence of sub-spaces) depends on a finite number of branches AND that the evolution of the universe can be described in terms of (the...

That is an assumption that you are not free to make. If you measure something with a digital instrument, it is true, but not if you use an analog instrument, or if you register events with the brain. In general, the wave function varies smoothly, and it lives in an infinite-dimensional space...

I see no reason to believe that there is only a finite number of branches. For instance, the time of decay of an atom has a continuous value, and each decay time corresponds to one branch, if measured.

Well, don't blame me what other MWI-proponents claim :smile: I believe that using probability in MWI is a choice, just as it is a choice to use probability when gambling. It isn't possible to prove in some fundamental sense that 1:1 is fair odds in a coin flipping game. You have to accept...

Yes, I guess that is true with regard to the practical utility of QM (but depending on what you mean by "to each branch at that time"). At each point in time you would have to assign a probability to each branch in the future of that time. That may be enough for practical purposes (but don't ask...

That's a good point. I want a theory to make sense not just now, but for any future time. One way to assure this is to include the infinity limit as well. I am not sure that the limit t->inf is strictly necessary, though. As long as the Hilbert space is infinitely-dimensional, you can in...

I beg to differ. Let me give you an example: Let the universe at any time have N+1 branches, where N is an unbounded, increasing function of time. Let one branch, called A, have a P-probability of 0.5. Furthermore, let each of the remaining branches (the union of which we call B) each have a...

The water wave is deterministic to an outside observer of the wave, just as the wave function of MWI would be deterministic to an outside observer. However, to an observer inside a universe according to MWI the future (as well as the past, btw) is indeed unpredictable. This is (as I understand...

Well, the fact that P and P' have measure 0 for different sets (i.e. they are not what I believe is called equivalent) is not a consequence of the choice of L2-norm. However, the fact that P is preferrable over P' obviously is. But, the L2-norm is natural as it is defined by the inner...