Far out cosmology: black hole theory proven (Introduction)

by David Turell , Tuesday, June 15, 2021, 18:57 (1044 days ago) @ David Turell

Stephen Hawking prediction about merging black holes proven:

https://www.sciencenews.org/article/gravitational-waves-confirm-black-hole-law-predicte...

"Despite their mysterious nature, black holes are thought to follow certain simple rules. Now, one of the most famous black hole laws, predicted by physicist Stephen Hawking, has been confirmed with gravitational waves.

"According to the black hole area theorem, developed by Hawking in the early 1970s, black holes can’t decrease in surface area over time. The area theorem fascinates physicists because it mirrors a well-known physics rule that disorder, or entropy, can’t decrease over time. Instead, entropy consistently increases

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"The surface area of a lone black hole won’t change — after all, nothing can escape from within. However, if you throw something into a black hole, it will gain more mass, increasing its surface area. But the incoming object could also make the black hole spin, which decreases the surface area. The area law says that the increase in surface area due to additional mass will always outweigh the decrease in surface area due to added spin.

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"According to the area theorem, the area of the newly formed black hole’s event horizon should be at least as big as the areas of the event horizons of the two original black holes combined.

"The team analyzed data from the first gravitational waves ever spotted, which were detected by the Advanced Laser Interferometer Gravitational-Wave Observatory, LIGO, in 2015 (SN: 2/11/16). The researchers split the gravitational wave data into two time segments, before and after the merger, and calculated the surface areas of the black holes in each period. The surface area of the newly formed black hole was greater than that of the two initial black holes combined, upholding the area law with a 95 percent confidence level, the team reports in a paper to appear in Physical Review Letters.

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"The area theorem is a result of the general theory of relativity, which describes the physics of black holes and gravitational waves. Previous analyses of gravitational waves have agreed with predictions of general relativity, and thus already hinted that the area law can’t be wildly off. But the new study “is a more explicit confirmation,” of the area law, says physicist Cecilia Chirenti of the University of Maryland in College Park, who was not involved with the research.

"So far, general relativity describes black holes well. But scientists don’t fully understand what happens where general relativity — which typically applies to large objects like black holes — meets quantum mechanics, which describes small stuff like atoms and subatomic particles. In that quantum realm, strange things can happen."

Comment: But despite Whitehead's warning theoretical math theorists still make correct predictions. However, whitehead's quantum theory comments still are correct, as the last paragraph notes.