I don't get this "infinite amount of time" thing. in a steady state universe, yes, sure, but if the expansion continues and no new incidents like the big bang happens, then it just gets colder and colder, right? and even if atoms were to come together in that way again, the CMB would be lower, so that fragment of timeline would lead to Pensias and Wilson to finish work earlier that day and never get the Nobel prize - so that history would be very different.