big-crunch

The universe has been expanding for 13.8 billion years, and dark energy is currently accelerating that expansion. If it suddenly reversed and the universe began contracting, we would be heading toward a 'Big Crunch' — but the change would be too slow for any individual to notice.

The universe began 13.8 billion years ago and will end — eventually. But how? Heat death, the Big Rip, the Big Crunch, and vacuum decay are all on the table. Here's what physics actually predicts for the final fate of everything.