One hundred trillion years have passed. No new stars are born. The remaining stars begin to fade out.

Through some quirk of extreme time travel I can detect cold dark matter. As more and more time passes, all that is left is black holes, sucking up any remaining material. My machine's dials cannot keep up with the movement of time. We are now many billions of times older than the universe was when the Earth existed. Heavier black holes are now sucking up the lighter ones.

Should I keep going even farther into the future? Or go back to my own time? Or do something else?