University of Queensland theoretical physicist Joshua Foo and his colleagues form the University of Queensland, Perimeter Institute and the University of Waterloo ran calculations that revealed surprising black hole quantum phenomena.
Foo et al. analyze the dynamics of a detector in a spacetime generated by a black hole in a superposition of masses. Image credit: Sci.News.
Black holes continue to captivate physicists from a diverse array of backgrounds, ranging from cosmology and astroparticle physics, to quantum field theory and general relativity.
Because of the extreme gravitational environments they generate, these compact objects are considered primary candidates for studying regimes in which quantum gravity effects are present.
Indeed, the discoveries of Hawking radiation and black hole evaporation gave rise to the well-known information paradox and an entire field seeking its resolution, which aptly illustrates the existing conflicts between quantum theory and general relativity.
Theoretical physicists recently recognized that a complete theory of quantum gravity must account for the treatment of black holes as quantum objects.
“Black holes are an incredibly unique and fascinating feature of our Universe,” said Foo, first author of a paper published in the journal Physical Review Letters.
“They’re created when gravity squeezes a vast amount of matter incredibly densely into a tiny space, creating so much gravitational pull that even light cannot escape.”
“But, until now, we haven’t deeply investigated whether black holes display some of the weird and wonderful behaviors of quantum physics.”
“One such behavior is superposition, where particles on a quantum scale can exist in multiple states at the same time,” he said.
“This is most commonly illustrated by Schrödinger’s cat, which can be both dead and alive simultaneously.”
“But, for black holes, we wanted to see whether they could have wildly different masses at the same time, and it turns out they do.”
“Imagine you’re both broad and tall, as well as short and skinny at the same time — it’s a situation which is intuitively confusing since we’re anchored in the world of traditional physics. But this is reality for quantum black holes.”
To reveal this, Foo and co-authors developed a mathematical framework allowing us to ‘place’ a particle outside a theoretical mass-superposed black hole.
Mass was looked at specifically, as it is a defining feature of a black hole, and as it is plausible that quantum black holes would naturally have mass superposition.
“Our research in fact reinforces conjectures raised by pioneers of quantum physics,” said co-author Dr. Magdalena Zych, a physicist at the University of Queensland.
“The work shows that the very early theories of Jacob Bekenstein, an American and Israeli theoretical physicist who made fundamental contributions to the foundation of black hole thermodynamics, were on the money.”
“He postulated that black holes can only have masses that are of certain values, that is, they must fall within certain bands or ratios — this is how energy levels of an atom works, for example.”
“Our modeling showed that these superposed masses were, in fact, in certain determined bands or ratios — as predicted by Bekenstein.”
“We didn’t assume any such pattern going in, so the fact we found this evidence was quite surprising.”
“The Universe is revealing to us that it’s always more strange, mysterious and fascinating than most of us could have ever imagined.”
Joshua Foo et al. 2022. Quantum Signatures of Black Hole Mass Superpositions. Phys. Rev. Lett 129 (18): 181301; doi: 10.1103/PhysRevLett.129.181301
Source : Breaking Science News