Professional physicists and astronomers claim there was a Big Bang beginning to the Universe (U). Since they weren't there and can't get a hold of it, most of the more discerning among them will call it a scientific "concept" upon which they build a edifice of "observed" and "observable" universe, the universe with a strict historical timeline. One timeline arrow with a supposed beginning in Big Bang and..... so far, ending in here and now, Earth 2021 (physicists' and astronomers' leading edge of time).
Based on the timeline of "observed" and "observable" universe their only timeline prediction is for a future of cold dead universe, no life at all left to it. The usual prediction of cold, dead, dead enders. The usual prediction of cold, dead, lifelessness.
Infinity, regarding the Universe (U), a. k. a. the Multiverse, is, of course, incapable of observation.... is unobservable and therefore must collapse in horizon regarding the observable.... regarding the foreground, the local, the relative, finite. What horizon? An objective and subjective what? An object where? An object when? That infinity implosively collapsed into finite horizon having what locally observable -- or predictable -- finite background object point and line physics?
Big Bang? CMBR? Redshift? Time (concerning the distantly collapsed -- to a Big Crunch point and line -- horizon, a timelessly endless beginning)? Universally constant constants ('c'....)?
The science of cold dead Universe isn't practical science. The religiosity of it is obvious. The obsessive religiosity of creationism is obvious whether any divinity is attached to it or not. Individually finite times (plural) do have beginning and end. The totaled up infinity of a pluralistic Time, non-linear Time, has no beginning and/or end.
Now some might try to say that "non-linear", the horizontal rank of vertical files (as in parallel universes), does not exist. What kind of mind would have you believe, would press you to believe (would dictate you believe), that there is no such thing as a non-linear Universe (that there is no such thing as an infinite Multiverse of infinitely paralleling universes within Universe's non-local, non-relative, 'unobservability')?