[Scientific research progress] The black hole dances "Square Dance", and the nature is revealed?——Shanda scientific research team in Shanghai Observatory has gained new progress in the study of double black hole gravitational waves

Recently, the gravitational wave research team of the Shanghai Astronomical Station of the Chinese Academy of Sciences through calculating the gravitational wave directly generated by the progress, and found that the spinning black hole twin stars except the LIGO (Laser Interfermeter Gravitational-Wave Observatory), laser interference with gravitational wave Observatory) In addition to the rotation of the screwdriver that is already well known to the astronomers, the gravitational waves that directly radiate the direct radiation of the black hole in front of the black hole. Related research results were published on September 3 on the Royal Astronomy Association Monthly (MNRAS Letter ".

In Einstein's general theory of relativity, gravitational waves are considered ripples of time and space, that is, the severe disturbance of the bending space -time, and spread out at the speed of light. In fact, in daily life, any quality object acceleration will produce gravitational waves, but very weak. However, the double black hole "dancing" is not the same. They will stir the time and space to turn around, radiating the gravitational wave that intensity is enough to be detected by humans. If the time and space of the universe is compared to the trampoline and the black hole to the trampoline athletes, then these black holes will jump around by turning around (nearly), collision (combined) on the universe. Time and space causes ups and downs, and the huge energy release in this process will be passed out in the form of gravitational waves. At present, the gravitational waves that are close -up and jointly emitted by Shuanghei Caves can be detected by LIGO (in order to exclude environmental signal interference, LIGO is composed of two interference instruments of LIVINGSTONSTONSTONSTONSTONTONSTONSTONSTONSTONSEAN LIVINGSTON and the HANFORD in the Northwest Coast of the United States. One with two 4 kilometers long arm and form L-shaped L-shaped, the signal is required at the same time), which corresponds to the classic IMR (Inspiral-Merger-Ringdown, near-parallel-bell) waveform [1]. From the perspective of the waveform, it seems that these double black holes "handle hands" dances, but the "dancers" are not shaking.

But sometimes, Shuanghei Hole will also jump "Square Dance", that is, the black hole shakes up. This phenomenon of dancing and shaking his head, astronomers call it "progress", in fact, the self -turning axis of the black hole changes in the spatial point of the space. The gravitational wave research team of the Shanghai Observatory started a research on the double black hole of the "Square Dance" in the lively place. By calculating the gravitational waves directly generated by the progress, the double black hole of the "dancing square dance" -self -spinning black hole Double Star-In addition to the recently detected by Ligo, the well-known spin-merged-bell-dangku gravitational waves also emit a gravitational wave due to the direct radiation of the black hole. Korean label researcher in the Shanghai Observatory Gravity wave research team explained: "A single black hole may have difficulty spinning, but the two black holes jump up the" square dance ", and the famous measurement effect will appear. As a result, the spin has a strong progress. "(As shown in the short video below)

Please click the short video below to view the schematic diagram of the black hole

Significant diagram of entering the black hole

(Made by open source software Precessing) [2].

Although the "square dance" of the two black holes can send this unique gravitational wave signal, due to the distant distance (the double black holes detected by Ligo are more than 100 million light years [3]), the signal reaches the earth It was already very weak. Dr. Zhang Chen, the first author of the paper and a special research assistant from the Shanghai Observatory, introduced: "Detailed calculations have a gravitational wave -shaped shape radiated by the progress itself. When the quality of the solar is greater than 80, the gravitational wave characteristics generated by the strong progress can be strong enough to make the signal -to -noise ratio of LIGO observed more than 10, which can be observed. This is a good news, which means that we can be on LIGO’s Ligo’s’s’s. Search this unique signal in the data. "The research team found that this signal suddenly broke out suddenly when it was approaching and closed. In the frequency domain, it also showed a significant difference in the IMR waveform. Therefore, IMR waveforms can be used as two. The signal issued by the black hole "jump" is the signal sent by the black hole when the black hole is swinging at the same time. "The essence of black holes is a very attractive major scientific issue. The general theory of relativity requires black holes. It only has two properties: quality and spin without charge. The gravitational waves from the spinning movement are completely the quality of the black hole. The distribution decision. Therefore, once we detect this gravitational wave, we can know whether the quality distribution of the black hole is consistent with the general theory prediction. This provides a new idea to study the nature of black holes through gravitational waves. The black hole dances the 'square dance', then its nature may be exposed. " Provide strong support. The excellent performance of the next generation of detectors makes this unique signal more sensitive, which will help understand the inner structure of the black hole, thereby revealing the nature of the black hole and testing the general theory of relativity. "

This project is supported by national key R & D plans and the National Natural Science Foundation of China.

Please see the original reading of the article link.

references:

[1] Buonanno a, COK G B, PRETORIUS F. Inspiral, Merger, and Ring-Down of Equal-Mass Black-Hole Binaries [J]. Physical Review D, 2007, 75 (12): 124018.

[2] https://vijayvarma392.github.io/binarybhexp/

[3] https://www.ligo.org/detections/

Scientific contact:

Korean standard, researcher at Shanghai Astronomical Observatory of Chinese Academy of Sciences, [email protected]

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