Scientists don’t have a crystal ball to help them foretell the future of the universe. But they can devise ideas about the future based on their understanding of the history of the universe and the laws of nature.
Based on that, perhaps the leading idea about the fate of the universe is the Big Freeze: The universe will get colder and darker, and eventually disintegrate into a soup of particles.
The key ingredient of the Big Freeze is dark energy. Scientists don’t yet understand its nature. But it causes the universe to expand faster as it ages. And if it keeps its foot on the accelerator, the universe faces a bleak future.
Hundreds of billions of years from now, the expansion rate will outpace the speed of light. Galaxies will disappear from each other – their light won’t move fast enough to reach most of the other galaxies.
The final stars will be born in a few trillion years. By then, most stars will have expired. Galaxies will consist mainly of the corpses of stars, plus some faint stars and smaller objects.
Over the eons, all the stars will die, and the stellar corpses will evaporate. And after trillions upon trillions of years, even black holes will vanish. Only ghostly particles will remain.
This future is far from certain. Scientists have many questions about dark energy and more. They’ll need to peer deeper into their crystal balls – the laws of nature – to tell us whether the universe will die in a Big Freeze.
Script by Damond Benningfield