Infinite number of planets with life

[Hovik]

I'm not wholly equipped to answer your questions as well as I'd like, but I can tell you that there is an "edge" to the universe in some sense.

Note that there are unanswered questions in this regard that make any answer to that particular question provisional. If the universe is flat, finite and otherwise geometrically compatible with having "boundaries", then reason tells you it must be bounded.

However, those questions remain unanswered to this day, though we do provisionally know that the universe is "close" to being "flat" (i.e. it's geometry is Euclidean), though it is not known to be. It is also not known to be finite (though it is suspected to be), nor can it's shape be described (particularly in terms of 3 dimensional geometry).

What lies "beyond" the boundary? Nothing. No matter, no energy, no entropy, no nothing. It simply does not exist. Anyone who thinks it's difficult to wrap thier brain around is correct.

Then again, if the universe is not flat, then it can be finite in size and still have no boundaries.

In that video I linked, Lawrence Krauss briefly discusses the shape of the universe and provides cursory evidence that it is, indeed, flat. However, I'm nowhere near qualified to say anything on the matter beyond taking his word for it.

Damn it Jim, I'm a linguist, not a physicist!