it's not known whether the Big Bang was the beginning of space or time. there's one theory (eternal inflation) that our universe fell out of a continuous Big Ba

it's not known whether the Big Bang was the beginning of space or time. there's one theory (eternal inflation) that our universe fell out of a continuous Big Bang when a false vacuum collapsed. all the pieces of that field then became particles, since they're high energy compared to the newly-dropped floor of our spacetime. the kind of expansion happening between galaxies is a different kind of inflation. it's even more mind-blowing though, because it would imply that the 10^-32 second inflation of our universe from a grain of sand to only 1000x smaller than it is now is just... the steady state, outside our microscopic bubble of observable reality.