Cosmology: time begins (Introduction)

by David Turell , Tuesday, May 27, 2014, 02:20 (3835 days ago) @ dhw

dhw: The website you've quoted contradicts you:-Not really. It is now considered that the hot big bang followed inflation. I was sloppy in what I said. From whatever began this universe for 10^-43 seconds there was inflation and then the hot big bang. Time begins with these events we theorize about. The quote is correct:
> 
> QUOTE: In fact, the particulars of this [data concerning the temperature of the universe] tell us that not only did time not begin at the Big Bang, but that we know what happened before the Big Bang: there was a period of cosmic inflation, where a tremendous amount of energy intrinsic to space itself dominated the Universe, and it expanded exponentially quickly at a fantastically large rate! 
> 
> dhw:Again, the bold is the author's, not mine, and he goes on to ask (among other questions): "did the inflationary state last forever going backwards?" Of course we don't and can't know, though he says: "It's even possible that time is cyclical, and that the cycles change with each iteration!"-IF there are iterations of a cyclical nature.
> 
> dhw: Final quote: "But even though we can trace back our cosmic history all the way to the moment of the Hot Big Bang, and even before that (a little bit) to the epoch of cosmic inflation, that's where our knowledge ends. So thousands of years later, we're right back to where we started."
> 
> dhw: On the assumption that you would regard inflation as an event, this can hardly be said to support the claim that time itself began with the BB. He is making the same point as me: we do not and cannot know when time began.-You interpretation is confused. We don't know what caused the inflation that began our universe but that is the beginning of our time. It is the first event (in theory) we count as in 'our' time. Further Einstein treats our universe as space-time and it is shown to work. Our space-time began with inflation.