A "black hole" validates Einstein's general relativity 10 years ahead of schedule: Space: Nature World News

September 15, 2019 22:52 EDT

For the first time, astrophysicists have heard a black hole ring like a bell. By re-analyzing the first black hole fusion ever detected, astrophysicists measured the "tones" of gravitational waves emitted as a result of the event. This breakthrough comes 10 years earlier than expected and confirms that the properties of black holes are in line with Einstein's predictions in his theory of general relativity of 1915.

"Previously, we thought these tones were too weak to be detected, we can do it now," says co-author of the study, Will Farr. "Just as the measurement of atomic spectra in the late 1800s opened the era of stellar astrophysics, classification and understanding of the stars, it is about the same. opening of the era of the spectra of black holes and the understanding of black holes and the general relativity that hides behind them. "

Farr is an associate professor at Stony Brook University in New York and a group leader in gravitational wave astronomy at the Computational Astrophysics Center at the Flatiron Institute in New York. He and his colleagues present their conclusions on 12 September Letters of physical examination.

When two black holes merge into one, the resulting oversized black hole swings like a struck bell. Reverbs emit gravitational waves with characteristic tones that fade as the black hole settles. The so-called & # 39; hairless theory & # 39; states that these tones – and all the other external properties of a black hole – only depend on the mass and rotation of the black hole, just as predicted Einstein's general relativity. Some scientists, however, suggest that the reality is more hairy and that effects like quantum mechanics also play a role.

Scientists knew that detecting the sound of a black hole could settle the debate. But the tones were deemed too quiet to be detected by the gravitational wave detectors of the current generation LIGO and Virgo.

In the new study, the astrophysicists combined simulations of blackheads with a reanalysis of the first gravitational waves ever detected. These waves came from the fusion of two black holes. The analysis led to the identification of two independent sounds emitted by the newly combined black hole. The pitch and fall rates of these notes align with Einstein's general relativity. The theory without hair has triumphed.

Farr says that with the new data analysis and that LIGO and Virgo continue to observe black hole mergers, observatory tests will become more accurate. The additional accuracy will likely lead to additional detections of black hole tones and a better understanding of exotic objects.

Farr collaborated with Maximiliano Isi of the Massachusetts Institute of Technology and astrophysicists Matt Giesler, Mark Scheel and Saul Teukolsky of the California Institute of Technology.