Physicists: black holes can turn into white ones

In a new study by researchers from the University of Sheffield and the University of Madrid Complutense notes, that black holes can turn into white ones.

When stars run out of hydrogen in the interior, they collapse, turning into a singularity with infinite density. Any material, whether gas or dust, is attracted to the singularity by gravity and cannot leave it.

Scientists call this point of no return the event horizon or radius Schwarzschild. In order to avoid black hole gravity matter has to move at a speed higher than the speed of light, which is virtually impossible. That is why such a singularity is called a black hole. Even light cannot leave them. That’s why they look like voids in space.

Traditionally black holes are considered to be endpoints in the Universe where matter, space, time, and energy disappear without a trace. However, a new study by British and Spanish scientists offers a new perspective on this strange physical phenomenon.

Scientists suggest that black holes can transform into white holes, spewing matter, energy, and even time back into the Universe. In areas of singularities, the laws of physics we are used to no longer apply.

In their research, physicists turned to the relatively new field of — quantum gravity, which seeks to unify general relativity with quantum mechanics. In particular, the scientists applied the theory of quantum gravity to describe what can happen inside a black hole.

The researchers focused on a particular type of black hole — a flat anti-De Sitter black hole, which has a somewhat simpler geometric structure, making it easier to study. The researchers based their analysis on the concept of unitarity, which implies that the total probability of all possible variants of a system’s structure must always be equal to one. This principle ensures that information will never disappear, even in the chaotic environment of a black hole.

Based on the requirements of the concept of unitarity, physicists have concluded that a classical singularity cannot exist. Instead, the internal part of a black hole enters a quantum state in which the singularity is replaced by a region of intense quantum fluctuationsany random deviation of any value. In quantum mechanics, a deviation from the mean value of a random variable that characterizes a system of a large number of chaotically interacting particles, known as «quantum bounce».

In this region, space and time are not finite, they are transformed into the so-called «white hole», which theoretically pushes matter and energy back into the universe.

«Hypothetically, you could make an observer go through a black hole, through what we consider a singularity, and come out the other side of a white hole. This is a very abstract concept, but theoretically it can happen», — explains the co-author of the study, Dr. Steffen Gielen from the University of Sheffield.

This idea is not new. A number of physicists have suggested that black holes can become white. However, this study provides a concrete mathematical justification for how this can happen. The researchers argue, that the mechanism of this process is consistent with the principles of quantum mechanics.

Everything in the physical world can work in both directions — this is one of the most profound features of the laws of physics, reflecting the elementary symmetries of space, time, and causality. If you send all parts of the system in the opposite direction, all actions will be rejected. The information to reverse time is always preserved. However, if black holes do not store information as they should, given that they are described as bottomless spatial holes, then physicists really have a problem.

Another interesting consequence of the theory proposed by scientists is that dark matter controls time. British and Spanish physicists suggest that dark matter can act as a universal reference point for measuring time. The study suggests that time is inextricably linked to the fabric of the Universe itself. Dark energy acts as its clock.

«In quantum mechanics, time, as we understand it, cannot end, as systems are constantly changing and evolving While time is generally considered to be relative to the observer, in our research, time comes from a mysterious dark energy that permeates the entire universe We assume that time is measured by dark energy, which is everywhere in the Universe and is responsible for its current expansion», — Steffen Gielen says.

This assumption not only offers a new perspective on the behavior of black holes, but also explains the potential connection between quantum mechanics and general relativity But what does it mean when a black hole turns into a white one? Could white holes be related to wormholes, hypothetical tunnels through space-time? Could they offer a glimpse into other dimensions or universes? The new study does not answer any of these questions, so it remains rather speculative.

The theory of unimodular gravity that the researchers used in this study is also a speculative branch of general relativity. So take it all with a grain of salt.

Ancient galaxies hint that the Universe originated in a black hole — by repeating the same motion

The article was published in the journal Physical Review Letters

Source: ZMEScience