The big bang theory is praised because of its capability of describing Universe development, rather than its birth, by explaining some observed phenomena (the main "proof" being the cosmic microwave background radiation).

And it could apply also to the hypothesis of an oscillating - i.e. cyclical - universe, and (I guess) allow for the presence of multi-verses. In other words, I fear that even assuming an oscillating universe you wouldn't necessarily get rid of it, except that it would also call for a big crunch (whose odds are currently low). I personally don't like inflation, nor the supposition of an inflaton elementary particle to justify it, but maybe it is just because I don't fully understand them.

I don't understand why you are speaking about multi-verses, which is a theory even worse than the Big Bang.

A logical comment would be a second Universe with inverse symmetry, i.e., an anti-Universe. This would render the symmetry correct. Of course, you could then imagine an innumerable number of such Universes but, this is not multi-verses.

The Big Crunch is not necessary if you can avoid the Big Bang. You will of cause have a variation of density in the extremes of size but, it doesn't need to be extremely violent.

JES

Dear Stellan,

all my apologies: I am only a layman in this domain, and I should have been more prudent in answering, including in the wording. What I meant is that big bang could also go along with the hypothesis of an oscillating universe (intended as cyclical, non just "oscillating" in a proper sense, as you hint).

kind regards

Andrea