Stephen Hawking’s death was a great loss to the world of science. The death of the scientist did not mean the end of his theories. His last theory on the origin of the universe has been published by the Journal of High Energy Physics. Professor Thomas Hertog from KU Leuven and Stephen Hawking collaborated on the paper which was submitted before Hawking’s death.
The ideas in the paper are based on string theory. It says that the universe is finite and the origin might have been simpler than currently imagined. Modern Big Bang theorists believe that the universe came into existence with a burst that occurred just moments before the Big Bang.
“The usual theory of eternal inflation predicts that globally our universe is like an infinite fractal, with a mosaic of different pocket universes, separated by an inflating ocean,” said Hawkins in an interview last autumn. “The local laws of physics and chemistry can differ from one pocket universe to another, which together would form a multiverse. But I have never been a fan of the multiverse. If the scale of different universes in the multiverse is large or infinite the theory can’t be tested.” In their new paper, Hawking and Hertog say the eternal inflation model is wrong.
This is due to Einstein’s theory of general relativity, which breaks down on quantum scales. “The problem with the usual account of eternal inflation is that it assumes an existing background universe that evolves according to Einstein’s theory of general relativity and treats the quantum effects as small fluctuations around this,” said Hertog. “However, the dynamics of eternal inflation wipes out the separation between classical and quantum physics. As a consequence, Einstein’s theory breaks down in eternal inflation.”
“We predict that our universe, on the largest scales, is reasonably smooth and globally finite. So it is not a fractal structure,” said Hawking. This latest research does not disprove multiverses completely but reduces them to a much smaller range.
It is nice to see that professor Stephen Hawking is continuing to make an impact in the world of science even months after his death. You can see what professor Hertog had to say in the video below: