But researchers say they have found evidence that its repulsive force may be weakening. According to their model, the universe could stop expanding for the next 65 million years. Researchers then believe that within 100 million years, the universe could enter a new phase of contraction for billions of years. This, they say, could signal the agreement of the universe and everything in it, or the rebirth of space and time. And all of this could happen “remarkably soon,” according to study co-author Paul Steinhardt. He said: “Going back 65 million years, it was then that the asteroid Chicxulub hit Earth and wiped out the dinosaurs. “On a cosmic scale, 65 million years is extremely short.” For now, it may be just a theory, experts say – as it is impossible to test. Dark energy has puzzled scientists for years trying to explain why the universe is accelerating. READ MORE: VDL faces nightmare as EU nations REFUSE to back new sanctions package on Russia Two things could happen after that, according to experts. Either the universe shrinks until it collapses on its own into a “Great Tragedy” that ends life as we know it – or, the universe shrinks enough to return to a state similar to its original conditions, and another Big Bang. The Big Crunch is not a new theory, but it has been set aside historically for lack of evidence. The new study, published in the Proceedings of the National Academy of Sciences, could change that.