How Many Worlds?

smk

How many universes "branch off" from a "quantum event", and in how many of them is the cat dead vs alive, and what about non-50/50 scenarios, and please answer so that a physics dummy can maybe kind of understand?

(Is it just 1 with the live cat and 1 with the dead one?)

Uncountably many. Consider that on the scale of the Omniverse (which contains only this one particular universe among uncountably many) the probability for any event is 1. It is also so, because it is absurd to suppose there is a universe in which something, if there be anything, does not exist. Furthermore, even if the probability for an event in our universe were 0 that would in no way serve as an impediment to its occurring in the long run.

I read your post in the other thread by Mitch_Porter, asking about why your post here got downvoted. As someone who would also have responded with the answer "uncountably many" and was in fact surprised to find that that wasn't quickly established as the obvious correct answer, I thought I might come take a look.

I would guess that the (mild) downvoting on this post comes from the fact that after your first sentence, you stop talking about specific instances of decoherence and start talking about omniverses and probabilities of 1 and 0. your lan... (read more)

-2mwengler14y

In fact there are many continuous outcomes in quantum mechanics. The overved velocity or momentum of an electron or any other mass. In fact the number of stated problems where the results are broken down in to discrete states is small compared to the ones with continua. In fact, the heisenberg cat example, there are not just two states of outcome, either alive or dead. Rather there are a myriad of state outcomes where the cat is alive, and another myriad of outcomes where the cat is dead. I personally think the many worlds hypothesis is ludicrous, failing Occams Razor by such an astonishing margin that it might as well just grow a long beard. Admittedly, I have not read any respected physicists argument for it (or at least I didn't respect the arguments I did already read). I think the many worlds hypothesis is just a very dopey hack for people who have decided ahead of time that the universe "just HAS to be" deterministic. I say if you observe indeterminism in the universe, then it is your theory that is broken, not the universe.

0prase14y

The answer is only true if the measured quantity has continuous spectrum, therefore not applying to the only explicitly mentioned example of the cat. Furthermore I don't follow your subsequent reasoning.