Hawking was right. Black holes do not shrink after collision

In his theory, Hawking assumed that the total occurrence horizon of any black hole would never shrink.

Scientists led by experts at the Massachusetts Institute of Technology (MIT) in Cambridge, USA, studied two black holes combined to form one large black hole, with a large amount of energy in space, such as gravitational waves. The Daily Mail reports that Hawking’s theorem on the area of ​​black holes was first confirmed by observing gravitational waves.

Physicists from MIT and other scientific institutes studied the impact of the collision or fusion of two black holes observed by gravitational waves. This is an event called GW150914 – the first detected signal of gravitational waves, detected in 2015 by the US laboratory LIGO.

The signal from GW150914, even with computer simulation, was explored before and after the cosmic collision of black holes based on the validity of Hawking’s theorem. With 95 percent confidence, the researchers found that the total area of ​​the event horizon did not actually decrease after the holes merged.

“Conversely, new calculations have shown that the total incidence of two connected black holes is greater than the sum of the two smaller holes in the underlying surface,” according to a recent study by Physics Review Letters.

The definitive result is as follows: The two black holes initially covered an area of ​​about 235 thousand square kilometers, after colliding 367 thousand square kilometers, according to the MIT website.

Hawking derived his 50-year-old hypothesis from Albert Einstein’s theory of relativity, which predicted the existence of gravitational waves and black holes. The current confirmation of Hawking’s theorem further strengthens the position of Einstein’s theory.

Newly obtained data confirm that the size of black holes does not decrease over time, so of course not everyone. Thus, with all the changes that occur in black holes, the area of ​​the phenomenon horizon should increase or at least not decrease – similar to the increase in entropy (the degree of disorder of the system), the scientific team says.

This was previously clear to scientists when a “normal” object fell into the black hole (the black hole expands, including the area of ​​the horizon), but in the case of the fusion of the two black holes add two parts.

It is also worth noting that Hawking (died March 14, 2018), who learned that the black hole fusion had been recorded, contacted Gip Thorne, co-founder of the LIGO at the California Institute of Technology. He wanted to know if he could confirm his theorem on the surface of the horizon from the detected gravitational waves. However, this technology is not yet available, which will allow data to be retrieved from the gravitational wave signal.

However, in 2019, Maximiliano IC from MIT came with him, and he was also the lead author of the newly published study. His technique made it possible to extract from the signal the “echoes” that follow the maximum from the signal. They were able to calculate the mass and vortex (velocity) of the resulting black hole, from the mass to the area of ​​the event horizon.

Physicist Thorne later referred to Hawking and said that the signal before the peak is similar to the original two black holes and should be analyzed similarly.

According to scientists, this is not an “irreversible and universal validation confirmation” of Hawking’s theorem because black holes and their connections can be of various types, but denial is not expected in the professional community.