The overall progression of matter goes from light to heavy through mass condensation.
This makes matter more radioactive, and therefore more readily fissionable. This in turn extends the life of stars. The gradual increase in radioactivity allows stars to function as electrical accelerators for longer.
However, the process of mass condensation cannot go on for ever. At some point, all elements will become radioactive. There will only be hydrogen left, all with enormous protons.
It seems unlikely that this is a sustainable state of matter. Such a situation begs for some correcting mechanism. My guess is that protons have an upper limit to their size, and that the proton itself becomes radioactive once that limit is breached.
Once protons start to collapse, a chain reaction ensues, and we get a massive burst of gamma-rays.
Bundled up with these gamma-rays, we find electrons and positrons that soon start the process of mass condensation all over again.
This is how quasars are formed. Over time, they become galaxies. The galaxies develop regions of degenerate matter. The matter collapses into radiation, and the cycle repeats.
This continuous process of creation, growth and destruction of matter solves the problem of heat death through entropy. It allows for a universe that is eternal, with no beginning and no end.