Yep! The observable universe has an edge we're fairly confident about. Though while it is absolutely "expanding", unfortunately, space around it is also expanding, so the universe is getting bigger in size, but we don't think we're gaining any new mass or exciting celestial objects. Everything's just getting further away..
But you can walk straight for all infinity. That's kind of my point when people talk about an infinite/finite universe they conflate the distance that can be travelled with the surface area/volume of it.
The universe is like in cartoons when they are chasing eachother in a hallway with many doors and they run in one door and come out of one on the opposite side.
Define Universe. Hubble Volume obviously finite. Current inflationary cosmos likely infinite in space but not in other dimensions. Entire substrate the cosmos comes from likely infinite along many more dimensions.
Entire substrate the cosmos comes from likely infinite along many more dimensions.
Agree with the first part of your comment but this last part... There's no experimental evidence whatsoever for other dimensions besides 1 time + 3 space so this is extremely speculative.
I mean, Time might be infinite, but it is bounded at least on one side and I suspect it's not bounded on the other.
In any case no one has evidence even for infinite space, for all we know it stops dead a Planck Length beyond the Hubble volume. Though this would require uh...extensive revision...of current models.
As for other dimensions, I'm using the term in the loosest possible sense to mean the substrate the current cosmos came from. It could have come ex Nihlo, of course, but it seems more likely it's part of a greater structure.
multiple inflationary events occuring outside the horizon of individual "universes"
so basically infinite sea foam of both ancient voids where protons barely exist anymore, mature universes with active star birth, and places with weird physics that fell apart quickly
over a long enough time frame, some of those ancient voids may light up again when some quantum tunneling event occurs