Cosmologist can rattle off answers as quickly and confidently as a schoolchild who has mastered his multiplication tables.
Question: How quickly are galaxies receding from each other?
Answer: .4 kilometres per second per megaparsec, plus or minus 1.8 per cent.
All right clever clogs
Questions: How old is our observable universe?
Answer: 13.75 billion years, plus or minus 0.8 per cent.
OK smarty pants.
Question: How much matter and energy fills the universe?
Answer: If one includes the weird and unwelcome dark energy in the tally, the total weighs in at precisely the razor-edge critical value, give or take 0.7 per cent, meaning that the universe should continue expanding for ever.
Expanding for ever!!! So is our universe getting bigger
Not only getting bigger but getting bigger faster. ('Dumbo' the cosmologist does not say this) Did you know (Dumbo) that for the first time in human history, scientists can date the age of the cosmos.
No, I didn't know that.
Well it does take an imaginative leap. Speaking of which Roger Penrose’s Cycles of Time takes one such imaginative leap. Rather than presume that the big bang of 13.75 billion years ago was the start of everything. The universe, he suggests, had already passed through innumerable previous instantiations before the big bang that started the present epoch, and that it will probably cycle on in this way for ever.
He argues that the end of one cosmic epoch or ‘aeon’ may look quite a lot like the beginning of another – so much so that perhaps they might be stitched together, end on end, into an infinite tower of repeating aeons
Penrose argues that our universe will almost certainly never recollapse on itself but continue to expand for ever.
Why don't you watch that vidwo on You Tube
https://www.youtube.com/watch?v=17jymDn0W6Ureally give you some idea of dimensions.
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