1 Iki Piki: So... You’re saying we’ve gone so far forwards in time that we’re witnessing the heat death of the universe.
2 Spanners: Oh, no, not at all! There are still black holes and dark planets close to absolute zero out there.
3 Spanners: It’ll take another 10⁴³ years for all the protons to decay. Then 10¹⁰⁰ or so more for the black holes to evaporate.
4 Iki Piki: Well. I’m glad we have something to look forward to.

Evidently in the Space setting science has advanced far enough from the present day that particle physicists are convinced that protons will decay.

In our present, proton decay is a theoretical possibility, but has not been experimentally confirmed. Currently the half-life of a proton before decay is constrained by experimental results to be greater than about 10³⁴ years, and also constrained by current theories to be below about 10³⁶ years. So there's a bit of wiggle room in there.