A star, more than three times the size of our sun, ought to end its life, how? With a collapse. The gravitational forces of the entire mass overcoming the electromagnetic forces of the individual atoms, and so collapsing inwards. If the star is massive enough, it will continue this collapse, creating a black hole, where the warping of time-space is so great that nothing can escape, not even the light. It gets smaller and smaller. The star, in fact, gets denser as atoms, even subatomic particles get literally crushed into smaller and smaller space. And at its end point what we are left with? A space time singularity. Space and time come to a stop.