Decoding the nearly 50-year-old black hole paradox

Hawking’s paradox states that when black holes disappear, they will destroy all information about their origin, contrary to the rules of quantum physics. To date, this paradox has been resolved.

According to theoretical physicist Stephen Hawking, black holes slowly disappear because they release an amount of radiation, called “Hawking radiation”, but in the form of thermal energy. Radiation can carry information about its source, but heat cannot. Therefore, when black holes gradually disappear, all information about the star that created them also disappears.

Information about the formation of black holes can be found in the form of radiation they emit.

Information about the formation of black holes can be found in the form of radiation they emit, according to new research explaining Hawking’s paradox. (Photo: NASA).

This contradicts the laws of quantum mechanics, which hold that information cannot be destroyed and that the final state of an object can reveal clues about its initial state. It’s called “The paradox of falsified information”.

Hawking’s paradox

Black holes are objects so massive that nothing can escape their gravitational pull, including light. They form when giant stars collapse on themselves.

In classical physics, black holes are considered very simple objects, which can be characterized by three numbers: mass, angular momentum and charge, explained Xavier Calmet, professor of physics at the University of Sussex. However, the original star that gave rise to the black hole is a complex astrophysical object, made up of protons, electrons and neutrons that combine to form the star’s chemical elements, Calmet noted.

The first image captured of a black hole

The first image captured a black hole, at the center of the M87 galaxy, nearly 54 million light years from Earth. (Photo: EHT Collaboration).

Although black holes carry no traces of these complex chemical elements, the rules of quantum physics dictate that the information cannot be erased from the universe. SO, In theory, from the radiation emitted by the black hole, it is still possible to recover information about the original complex star..

In 1976, Stephen Hawking “broke” this rule when he said that black holes continuously emit a certain type of radiation. This radiation leak causes black holes to gradually evaporate and disappear completely. But this radiation is emitted as heat, meaning all information about the star that created the black hole is also gone.

“This goes against the rules of quantum physics, which say that the ‘life’ of a black hole can be rewound and that, thanks to radiation, it is possible to reimagine the black hole and the star that surrounds it. ‘created.”Calmet said.

Decoding the black hole paradox

Calmet spent nearly 3 years decoding Hawking’s paradox. In the new study, he re-evaluated Hawking’s 1976 calculations, but this time taking into account the impact of “quantum gravity” – describe gravity according to the principles of quantum mechanics – which Hawking did not do.

“Even though these quantum gravitational corrections are very small, they are important for the evaporation of the black hole. We were able to show that these effects mean that Hawking radiation is no longer thermal energy and can contain information. »Calmet said.

Calmet’s team also identified the physical phenomenon by which information escapes from black holes via Hawking radiation, and how an outside observer can recover this information to reconstruct the original black hole and star. However, this process cannot be carried out in practice, because it requires a device sensitive enough to measure Hawking radiation, which does not currently exist.

Article source: Zing