Multiverse?

[TaO!]

I have an interesting though, or rather a question, on there being a multiverse or universe in a quantum superposition. This arises, of course, from the Copenhagen interpretation of Quantum Mechanics (QM). Now skipping a whole load of unnecessary explanation for the sake of brevity, and some peoples sanity, are they essentially hypothesising an enormous number of simultaneously existing states like something out of a sci-fi flick that we can't detect like an infinite number of non-observable alternate universes?

[PoodleLovinPessimist]

Cosmological Multiverse Theory (http://www.google.com/search?q=multiverse+cosmology) is different from the Many Worlds Interpretation (http://www.google.com/search?q=%22many+worlds+interpretation%22+%22quantum+mechanics%22) of Quantum Mechanics.

See also the Wikipedia articles on the Multiverse (http://en.wikipedia.org/wiki/Multiverse) and the Many Worlds Interpretation (http://en.wikipedia.org/wiki/Many_Worlds_Interpretation).

[|2eason]

Afaik, a cosmological multiverse stems from finetuning and anthropic argument. Ie, this universe seems precisely finetuned for life, but it would do because life is present, and this suggests there may be a number of other universes with different constants. But, we do not understand yet WHY it is finetuned for life. It might because it can be no other way. Frankly, I don't think we have enough knowledge of physics to assert multiverse theory.

MWI is just one of many theories put forward to explain wave/particle duality. Frankly they could all be wrong, but for now I prefer feynmans. To the OP tho, I don't think MWI suggests an infinite number of real universe, just 'unrealised' ones. Whatever the hell that means. :confused:

[Dark Knight Bob]

You then of course have the other type proposed to explain the paradox's proposed by time travel if it is possible.