Black holes, celestial objects so compact that the intensity of their gravitational fields does not allow any form of matter or radiation to escape, envelops both scientists and amateurs. Among the many riddles they store, the mystery of their death is one of the most intrigued ones. Stephen Hawking has demonstrated the likelihood that black holes will be volatilized and vanished, but unfortunately, in contradiction with the general relativity: this is an information paradox. Recently, a group of researchers has used a theory known as "gravity of Einstein-dilton-Gausss-Bonne" to examine the final states of evaporatord black holes. Their discovery, which has yet to be confirmed, allows a new look at these celestial objects.
The black hole is a celestial object whose gravity is so powerful that it absorbs everything behind its "horizon of events", including light. These celestial objects are an integral part of the structure of the universe. The powerful gravity created by black holes arises because matter has been compressed in tiny space. It can occur at the end of life of stars, so that many black holes are the result of the death of stars. In fact, in the center of most galaxies, including our own, there are black holes. But we still don't know how these objects die.
Stephen Hawking has demonstrated the possibility of evaporating black holes, a phenomenon that he called Hawking's radiation, in other words, the radiation that emits any black hole in accordance with the laws of quantum mechanics and that causes it to evaporate by losing mass, the angular moment if the black hole rotates, and the electrical charge if it is charged.
But according to the general theory of relativity, it is impossible, because nothing that enters the horizon of black hole events can leave it. However, this theory predicts the existence of points of infinite density where the laws of physics are broken: singularities. This is what is seen in the center of black holes, where all the matter of the star is concentrated. What happens when the black hole vanishes? Scientists have used a certain theory to study these final states. Their results are available on the website and await an expert assessment.
A new theory to understand the death of black holes
Thus, the emergence of Hawking's radiation created an information paradox of black holes. In March 2022, scientists made a hypothesis that black holes do not forever absorb information that enters them, but rather capture it in their gravitational field.
In addition, if you study Hawking's radiation, you could understand the physics of singularity, potentially containing information absorbed by a black hole. As the evaporating occurs, black holes become smaller and smaller, and their horizons approach central singularities. In the last moments of life, the black hole becomes too strong, and the black hole itself becomes too small to be described and understood from the lens of current knowledge.
Of course, relativity and quantum mechanics don't work very well together, but using the various elements offered by these two theories is a possible way forward. There are many candidates for creating quantum gravity theory based on a modified general relativity theory.
The details of the team's results are unfortunately somewhat unclear. Indeed, the modified general relativity is not as well understood as the classical general relativity, and the solution to the equations is based on many assumptions. However, researchers were able to describe the death of a black hole according to its nature and evolution.
It should be noted that one of the main features of the gravity theory of Einstein-Dilaton-Gaussa-Bonne is that black holes have a minimum mass, so the authors were able to study what happens when the evaporator black hole begins to reach this minimum mass.
So, on the one hand, the evaporative process can leave behind a residual "microscopic nuclei" that has no horizon of events. The authors believe that in theory it will be possible to restore this "sumour" that contains all the information that has entered the original black hole and thus resolve the information paradox. On the other hand, the black hole can reach its minimum mass and get rid of the horizon of events while preserving its singularity. These "naked singularities" appear to be prohibited in the general theory of relativity, but if they exist, they will be a direct window into the realm of quantum gravity.
Pending confirmation that the gravity of Einstein-Dilaton-Gaussa-Bonne may be a valid route to quantum gravity, results such as those presented in this study will help physicists to develop reliable scenarios of the evolution of black holes.