Who are the "Firstborn" as noted in the book, Time’s Eye?

Firstborn was the name given to the beings responsible for the Discontinuity by those left behind. The Firstborn are almost as old as time itself, having been born on a planet around one of the first stars in existence. Despite all their powers, they are unable to pass beyond the reach of time, and they become aware that they are stranded and left to watch a slow darkening of the skies as the fuel that powers the Galaxy slowly runs out. They cherish life above all else.