A group of researchers has shown that Black Holes are home to weird vortex-like structures, adding fuel to the mystery surrounding black holes.

A black hole is a huge astronomical object whose gravitational pull is so strong that even light cannot escape. Despite the fact that black holes have been known since the 18th century, it was only in 2015 that they were directly observed for the first time.

A number of theoretical and experimental studies have been conducted since then in an effort to better understand these fascinating cosmological objects. A variety of theories and discoveries have been made about the dynamics, properties, and characteristics of black holes.

Recently, Ludwig-Maximilians-Universität and the Max-Planck-Institut für Physik conducted a theoretical study exploring the possibility that black holes have vortices. They propose that black holes should be able to support vortex structures in their paper published in Physical Review Letters.

Florian Kühnel, one of the researchers who conducted the study, told Phys.org that a new quantum framework for black holes had been introduced based on Bose-Einstein condensates of gravitons. “Until this research was published, rotating black holes hadn’t been well studied within this framework. However, they might not only exist, but they might also be the norm instead of the exception, Kühnel added.

Based on existing physics theories, Kühnel, Gia Dvali, and Michael Zantedeschi carried out several calculations, particularly the recently developed Bose-Einstein graviton condensates quantum model of black holes. To determine whether rotating black holes would actually admit vortex structures, they examined them at the quantum level.

The first image of the supermassive black hole in the center of the Milky Way – Sagittarius A*. Credit: ESA

As a result of intensive laboratory research, rotating Bose-Einstein condensates can exhibit vortex structures if they are rotated sufficiently fast, Kühnel explained. The research led scientists to look for those structures in rotating black hole models as well—and they did.

A black hole with extreme spin can be described as a graviton condensate that is vorticious, according to Kühnel and his colleagues. According to previous studies, extreme black holes are stable against what is known as Hawking evaporation, a type of black body radiation believed to be released outside the event horizon of the black hole.

As a result, the researchers discovered that the black hole’s overall vortex traps the magnetic flux of the gauge field when there are mobile charges, which produces signature emissions that can be observed experimentally. Thus, new types of matter, such as millicharged dark matter, could be observed based on the team’s theoretical predictions.

“On the classical level (that is, if one closes their eyes to the quantum structure) black holes are fully characterized by three entities: mass, spin, and charge,” Kühnel said. “The textbooks taught us this up until now. We have shown that it is necessary to include vorticity.”

According to the team, the absence of Hawking radiation can be explained by vortices in black holes. By advancing this theory, new theoretical and experimental findings could be made in the future.

Observations of extremely strong magnetic fields emerging from active galactic nuclei could be explained by black hole vortex structures. Aside from that, they are likely to be responsible for nearly all galactic magnetic fields known to date.

In light of the fact that black hole vorticity is just a newly established field, Kühnel emphasized the importance of addressing a wide variety of important and exciting questions, such as those related to the applications mentioned above. A gravitational wave observation of merging black holes containing vortices, each containing multiple vortices, may also provide insight into these new physics.