The universe is not only expanding, it’s accelerating because of a mysterious force dubbed dark energy. The prevailing theory is that dark energy density will remain constant and so will expansion. The universe will experience a very slow heat death that will begin in approximately in 1016 (100 trillion) years and end in 10100 years. An opposing theory is that the density will increase and the expansion will accelerated so fast that in just 22 billion years all matter and space-time itself will rip apart, known as the “Big Rip.” Another possibility is that the density will increase but level off or slow down known as “Psuedo Rip” and “Little Rip,” respectively. In both of these cases, all matter is destroyed but space-time remains intact, leaving a vast nothingness.
However, the end of the universe could just be the beginning, according to a new study by Hao Wei of Beijing Institute of Technology in China.
“Our universe has a chance to be rebuilt from the ashes after the terrible rip,” says Wei. “This might be the last hope in the ‘hopeless’ rip.”
This phoenix-like universe would be result of a “Quasi Rip,” in which dark energy density decreases and slows the acceleration before space-time rips.
“The gravitational force glues the ashes into new structures, and the universe can be rebuilt,” he explains.
Scientists will have a better idea which is the more likely scenario early next year when the Planck satellite team publishes its analysis of background radiation left over from the Big Bang.
