JavaMan writes:
I've always assumed that the universe has been exanding for aeons, and millions of universes have been born and died on the way.
Shouldn't that be: "millions of
galaxies have been born and died on the way"?
[...] the timeline I've outlined in the opening post suggests to me either that the universe is far older than suggested by Big Bang theory, or that life is far more likely to develop than we customarily assume.
It's a bit tenuous to conclude anything about the likelihood of life from our only known example of it. Suppose there is a vase with red and blue marbles in it, in unknown quantities. You draw one marble. Upon finding that your marble is red, can you conclude anything about the likelihood of drawing a red marble?
"Ignorance more frequently begets confidence than does knowledge: it is those who know little, not those who know much, who so positively assert that this or that problem will never be solved by science." - Charles Darwin.