Theoretical physicists argue that black holes admit vortex structures

Black holes are astronomical objects with extremely strong gravitational pulls from which even light cannot escape. While the idea of ​​light-trapping bodies has been around since the 18th century, the first direct observation of black holes was in 2015.

Since then, physicists have conducted countless theoretical and experimental studies aimed at better understanding these fascinating cosmological objects. This had led to many discoveries and theories about the unique characteristics, properties and dynamics of black holes.

Researchers from Ludwig-Maximilians-Universität and Max-Planck-Institut für Physik recently conducted a theoretical study exploring the possible existence of vortices in black holes. Their article, published in Physical examination lettersshows that black holes should theoretically be able to admit vortex structures.

“Recently, a new quantum framework for black holes, namely in terms of Bose-Einstein graviton condensates (the quanta of gravity itself), has been introduced,” said Florian Kühnel, one of the researchers. who conducted the study, at Phys. org. “Until the publication of our article, rotating black holes have not been studied in depth in this framework. However, they could not only exist, but also be the rule rather than the exception.”

Kühnel and his colleagues Gia Dvali and Michael Zantedeschi performed several calculations based on existing physical theories, in particular the recently devised quantum model of black holes based on Bose-Einstein graviton condensates. The main goal of their study was to examine rotating black holes at the quantum level, to determine if they would actually admit vortex structures.

“Since rotating Bose-Einstein condensates have been extensively studied in laboratories, they have been known to admit a vortex structure if they rotate fast enough,” Kühnel said. “We took this as an invitation to look for these structures also in rotating black hole models – and indeed we found them.”

Kühnel and his colleagues showed that a black hole with extreme spin can be described as a graviton condensate with vorticity. This is consistent with previous studies suggesting that extreme black holes are stable against so-called Hawking evaporation (i.e. black body radiation that would be released outside the outermost surface of a black hole, or event horizon).

Additionally, the researchers showed that in the presence of moving charges, the black hole’s global vortex traps a magnetic flux from the gauge field, which would lead to experimentally observable signature emissions. The team’s theoretical predictions could thus open up new possibilities for the observation of new types of matter, including millicharged dark matter.

“Vorticity is an entirely new characteristic of black holes, which are at the classical level (i.e. if we close our eyes to their quantum structure) entirely characterized by three entities: mass, spin and charge,” Kühnel said. “That’s what we’ve learned from the textbooks – so far. We’ve shown that we need to add vorticity.”

The team’s theorized existence of vortices in black holes offers a possible explanation for the absence of Hawking radiation for maximally rotating black holes. In the future, this theory could thus pave the way for new experimental observations and theoretical conclusions.

For example, the vortex structures of black holes could explain the extremely strong magnetic fields emerging from active galactic nuclei in our universe. Moreover, they could potentially be the origin of almost all known galactic magnetic fields.

“We have just established the black hole vorticity field,” Kühnel added. “There are a host of important and exciting issues to discuss, including around the applications mentioned above. and exciting quantum aspects of space-time.”

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