How can one recognize multiverse

cosmology: Evidence for the multiverse

Cambridge / Vienna. (est) Stephen Hawking's thoughts on the creation of the cosmos accompanied Stephen Hawking to his deathbed. His final work could become his greatest legacy. Ten days before his death at the age of 76 on March 14, the famous British physicist completed calculations on the basis of which the existence of a multiverse could be proven.

In the work entitled "A Smooth Exit from Eternal Inflation" the cosmologist takes up one of his earlier theories about the creation of the universe after the Big Bang. According to her, today's cosmos emerged from a tiny point through a rapid expansion that astrophysicists call inflation. Hawking's hypothesis was that an infinite number of simultaneous big bangs must result in many parallel universes - some empty, others full of black holes, others with galaxies, stars, planets and possibly life.

"Each of our scientific models of the Big Bang leads to the formation of a multiverse. It is much more plausible that the Big Bang created many worlds than that there is only one. We live in one of many worlds," explains Hawking's co-author Thomas Hertlog in an interview with the British BBC.

Every good scientific model contains predictions about the properties of our cosmos. According to the Belgian physicist at the University of Leuven, multiverses are "something like the nightmare of cosmologists. If the multiverse is too gigantic or extremely different from the universe we know, the Big Bang theory says nothing about us." Nevertheless, the models cannot avoid a multiverse. "It is very difficult to consistently claim that we are alone," emphasizes Hertlog: "We therefore have to transform the concept so that the multiverum fits into a testable scientific theory. This is the question our work is about."

In the paper, Hawking and Hertlog set out the mathematical basis for an experimental proof of parallel universes. According to the theoretical work, these should be measurable in the cosmic background radiation that reverberates from the Big Bang. A space probe with the right sensors on board could travel into space for this purpose.

A first version of the work was published in July of the previous year in the online library "arXiv" at Cornell University. It has been updated over the past few months and, according to the "Sunday Times", has been sent to a renowned specialist journal for publication. Hawking also predicts the fate of our universe, which will sink into darkness when all the stars have lost their energy. The paper is currently being checked for plausibility by specialist colleagues. If it can convince, it would be a first step towards a completely new cosmic understanding.

Our place in the cosmos

The existence of parallel universes would redefine our own place in the universe. Their proof would qualify Hawking and Hertlog for the Nobel Prize as well. Hawking was denied this throughout his life because there was no evidence for his theories. Posthumously, however, the pop star among physicists could not get the award, as it is only given to living scientists.

Hertlog, who was Hawking's PhD student at Cambridge University in 1989, reports on a continuous collaboration with his professor. "We found each other early on in cosmology and saw each other every three to four months to sit shoulder to shoulder for hours exchanging ideas and calculations. In the end, when communication became very difficult, I felt we weren't like that took many words to communicate. "

Hawking is buried in Cambridge in March. Around 500 mourners are expected, including Internet inventor Tim Berners-Lee, physicist and science educator Brian Cox, and Hollywood star Eddie Redmayne, who played Hawking in "The Discovery of Infinity".