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dilletante said:I may be missing something but the reason I don't like the idea of a ONE-BOUNCE CYCLIC is because it seems to require two theories for the origin of a universe. The "bounce explains universe number two, but now you have to come up with a different theory for how universe number one, the contracting one, came into being. Assuming it didn't start out fully formed and infinitely large.
The conservation of dark energy is something that bugs me. I can only conceive of 3 possibilities, the third of which is inane:
1) The law of conservation of energy is incorrect.
2) Dark energy does not exist and we need a Reuter-like solution for inflation.
3) Dark energy pre-existed and is what the universe is expanding into.
It seems safe to discard 1) and 3).
I appreciate the way you are wrestling with these difficult questions, which I would describe as mentally vigorous. the conservation of energy thing bugs me too. There is something about it at John Baez site. We talk about it here sometimes. It seems that GR does not have a global energy conservation law! (nor does it have one official global time-clock, things have their own time that is proper to them but there is no comprehensive time). When one works with the universe as a whole, so far that means working within the GR context! So we have to get along without a complete energyconservation idea. It works locally in some particular frame of reference or in some region you can isolate from the rest, but not globally.
All the violations of energy conservation I know of share the aspect that it would be impossible to exploit them by any imaginable "perpetual motion" machine and thus to extract useful work. In the reference frame of the machine energy would be conserved basically so you couldn't get anything from it. Sometimes this seems amusing in a tantalizing way.
I'm glad you come to the same tentative conclusion that I do---which would be #2 among your alternatives.
About what you say at the beginning. I don't look to cosmology in particular or science in general to explain for me why the universe exists---or if it was simply always there---or if and how it came into "being". I just take for granted that it exists and I want to know about it.
that includes pushing back to time and events prior to bang
So the ONE BOUNCE CYCLIC is basically as good as any other, in this respect, for me. It has no more and no less untied loose ends.
however I have this unavoidable feeling that the black hole origin picture is more FUN. More fun to think about universes evolving so that they manage to produce lots of stars and thus lots of stellarcollapse black holes and thus lots of babies. it has the evolution angle that Smolin wrote about in the book Life of the Cosmos.
and its just fun to think about . this should not influence me as a sober critical person but it probably does.
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