The universe will not end for another 2.8 billion years, at least. University of Lisbon researchers say that the end would be caused by the dark energy accelerating the universe’s expansion, which will eventually kill stars, drift everything apart and cool down the universe.
The study involved modelling scenarios regarding different ways the universe could end. Scientists have speculated that the universe could end with the “big rip” where everything in the universe, including stars, galaxies and atoms, is gradually torn apart by the expansion.
However, this new study has shown that the big rip would never happen. Instead, the universe would end in a process called “heat death,” also known as the Big Freeze or the Big Chill.
“The ‘heat-death’ of the universe is when the universe has reached a state of maximum entropy. This happens when all available energy (such as from a hot source) has moved to places of less energy (such as a colder source). Once this has happened, no more work can be extracted from the universe,” Physlink.org explains.
“We show that quite generally, the lower bound for the singularity time cannot be smaller than about 1.2 times the age of the Universe, what roughly speaking means approximately 2.8 [billion years] from the present time,” the study authors wrote.
This study contradicts theories that claim that the sun will die within the next five billion to seven billion years, when it burned up all of its hydrogen fuel supply. At this point, the sun would inflate into a red giant and would swallow up everything nearby, including the Earth.
“Earth will end up in the sun, vaporising and blending its material with that of the sun,” says Iowa State University scientist Lee Anne Willson. “That part of the sun then blows away into space, so one might say Earth is cremated and the ashes are scattered into interstellar space.”