As for the 2nd part, we think the expansion of the universe is accelerating, which is effectively what “dark energy” is – an extra energy term in the equations designed to make the observations fit the theory. So a Big Crunch is unlikely unless our theory is wrong, which is entirely possible, though we’d have to explain why the theoretical fit to the data (with dark energy included) is so good.

Damn you space. Damn you for inflating us out of our greatest future-accomplishment!

On a more serious note: By your post above I guess it’s safe to assume that inflation has stopped, or at least slowed to the point of nearly stopping? Perhaps this is a good sign; an omen for those of us that naively hope for an endless cycle of Big Bang and “Big Crunch”. I mean, even with the infinitesimally small odds, at least it gives me another shot at this incredible ride, right? Hell, I was here once, that’s for sure!

*I think that’s a much more exciting moniker. You can use that around the office if you like.

(This is different from the observable universe in that the observable universe covers all light that has been emitted over the history of the universe. The Hubble volume on the other hand covers light that is emitted from objects *now*, and as such is about a third the size of the observable universe.)

Also, if the universe is big enough, there should be a distance that you could never reach or see, right? The light that travels this distance would go with the same speed the distance is getting bigger. So there should be some theoretical size of universe beyond which we’ll never would see anything, am I right?

(Note: the Big Rip is conjecture at the moment and is in no way a legit thing. It’s just useful for illustrating how expansion could possibly grow out of control.)

As to your second point, the speed of light is a constant, and it’s still a very large number. It will always govern all the processes that matter to us on human scales — so in a billion years time subatomic processes and whatnot will still function exactly the same way as they do now. However when you look at things on a universal scale the speed of light could begin to pale into insignificance when compared to the speed of expansion of space, leading to the rather comical Big Rip scenario referred to above.

Fast forward to the present day, and we’re just now “rediscovering” areas of the universe that we’ve been out of touch with ever since that first second. This is how we can see back to (and possibly past) photon decoupling at the 300,000 year point; this happened *after* inflation, and so there are regions of the universe where it took place beyond our observable horizon — so we were never part of those events in the first place. It’s the light from those regions that is reaching us now and is forming the cosmic microwave background radiation.

This isn’t the best explanation of a very counterintuitive concept, so do feel free to enquire further if you’re still puzzled by it all.

And so here goes even more mindblowing thing: if the first is right, how does it affect all those subatomic processesand powers? If the latter, is the speed of light becomes more insignificant each minute or does it scale with space?

“…so peering back past that 300,000 year barrier is going to be impossible using our current observational methods…”

How can we “peer beyond” what has already happened? (Terrible analogy ahead) It’s a bit like saying: if the universe is an ocean, and we’re a tiny plankton in the year 2013, we can develop a periscope powerful enough to see Magellan’s voyage through the Pacific. I understand that much of the universe we “see” today isn’t actually there at all, given the length of time the light waves took to get to us, but how can you ever expect to “see” events that we* were presumably a part of when they happened (300,000 years after the big bang, for instance)? I can’t wrap my head around that.

*By “we” I mean our particles and dust and such, not humans or our solar system or anything.