Far out cosmology (Introduction)

by dhw, Sunday, February 02, 2014, 13:08 (3946 days ago) @ David Turell

George (to David): The error in your thought processes here is not realising that time is an aspect of the universe. You are assuming the existence of infinite Newtonian (or Aristotelian?) time outside the universe. As one traces back the history of the universe from within it seems that one reaches a situation where time no longer exists, or becomes non-directional or indeterminate. That's the only solution that makes sense to me. -DAVID: I understand that time began at the Big Bang, and we live in a spacetime universe. And I also understand the Guth-Borde-Valenkin's paper at Hawking's 60th birthday says they could not find a 'before' before the Big Bang, or as they put it, 'a past incomplete'.. Further, Valenkin in the very recent past, last year, has produced a paper that states whether this is a solitary universe or a multiverse there is no 'before'. I still have a problem with something from nothing. A singularity is not a nothing. I am assuming a past without time, that has always existed.-I find this discussion difficult to follow. How are you defining time? The issue for me is not time on its own but time linked to cause and effect. If the Big Bang happened, it must have had a cause. You cannot have cause and effect without before and after. No-one knows what happened or what existed before the Big Bang. If physicists can postulate unknowable multiverses in our present, why shouldn't we postulate unknowable universes or multiverses in the unknowable past? "Past" and "present" are temporal concepts, but that doesn't have to mean time as measured and experienced by us humans in our particular universe. Claims that there was no 'before' the Big Bang (= no past) are as speculative and as unprovable as claims that there are parallel Georges and Davids in parallel universes, that first cause energy is conscious of itself, and that there is an invisible teapot orbiting the sun.
 
However, I would go one step further. I find it inconceivable that the Big Bang should not have occurred without a cause, and that there was no such thing as a before (and after). Consequently, I find it inconceivable that there can ever have been pure nothingness since, as David argues, nothing can come out of nothing. This means there must have been "something" for ever and ever. And for me the most likely "something" is energy transforming itself into matter. George defines energy "in terms of dimensions of mass, time and length." Since energy can take many different forms, I wouldn't know how to define it, and I certainly wouldn't endow it with any personal qualities, but I see no reason to assume that it has not been doing whatever it does for ever and ever.