Collaboration between European Southern Observatory and EHT
It turns out that Sagittarius A*, the supermassive black hole at the center of our galaxy, is spinning and dragging space-time with it.
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A new study shows that Sagittarius A*, the supermassive black hole at the center of our galaxy, is rapidly rotating and changing space-time around it.
Spacetime is a four-dimensional continuum that describes how we see space, merging one-dimensional time and three-dimensional space to describe the fabric of the universe that curves in response to massive celestial bodies.
A team of physicists observed a black hole. 26,000 light years from Earthwith NASA Chandra X-ray Observatory, a telescope designed to detect X-ray radiation from hot regions of space. They calculated Sagittarius A*’s rotation rate using the so-called outflow method, which examines radio waves and X-ray emissions in the material and gas surrounding the black hole, known as the accretion disk.to the study Published in Monthly Notices of the Royal Astronomical Society on October 21st.
Researchers confirmed that the black hole is rotating, causing a phenomenon known as the Lens-Sarling effect. The Lens Surling effect, also known as frame drag, is a phenomenon that occurs when a black hole drags space-time as it rotates. Ruth Daly, lead author of the study, said:professor of physics at Pennsylvania State University, Outflow method More than ten years ago.
Since the invention of the outflow method, Daly has been working on determining the spins of various black holes. 2019 survey We have investigated over 750 supermassive black holes.
“This rotation would cause Sagittarius A* to dramatically change the shape of spacetime in its vicinity,” Daly said. “We’re used to thinking and living in a world where all spatial dimensions are equal: distance to ceiling, distance to wall, distance to floor. They’re all kind of linear. Yes, but it doesn’t mean that any of them are equivalent.Compared to the others, they are completely crushed.
“But if you have a rapidly rotating black hole, the spacetime around it isn’t symmetrical. A rotating black hole is dragging all of the spacetime around it. It’s squashing spacetime, making it look a certain way. “It’s like football,” she said.
While changes in space and time are nothing to worry about, uncovering this phenomenon could be very helpful to astronomers, Daly said.
“This is a great tool for understanding the role black holes play in the formation and evolution of galaxies,” she said. “The fact that they are dynamic entities that can rotate…and that could affect the galaxy in which this exists is very exciting and very interesting.”
The spin of a black hole is given a value between 0 and 1. 0 means the black hole is not spinning, and 1 is the maximum spin value. Until now, there has been no agreement on the value of Sagittarius A* spin, Daly said.
Daly said the outflow method is the only method that uses both information from the outflow and information from matter near the black hole, giving Sagittarius A* spin angular momentum values between 0.84 and 0.96. It turned out that M87* — the black hole of Virgo Galaxy Cluster It was found to be 55 million light-years from Earth, rotating with a value of 1 (larger uncertainties are plus or minus 0.2), and close to the maximum value of its mass.
The researchers found that the two black holes rotate at similar speeds, but M87* is much more massive than Sagittarius A*, so Sagittarius A* can cover less distance. Daley said the M87* has more revolutions per revolution.
Sagittarius A* is “spinning much faster[in comparison]not because it has a higher spin angular momentum, but because it has less distance to travel in one revolution,” Daly explained. .
History of black holes and galaxies
Knowing a black hole’s mass and rotation can help astronomers understand how black holes formed and evolved, Daly said.
Black holes that are formed as a result of the merger of smaller black holes typically exhibit low spin values. Dejan Stojković said.He is a professor of cosmology at the University at Buffalo, but was not involved in the study. However, black holes formed by the accretion of surrounding gas exhibit high spin values.
Sagittarius A*’s rotation rate would indicate that a significant portion of the black hole’s mass came from accretion, he said.
“The question of whether and how fast the black holes at the centers of galaxies rotate is of great importance,” Stojković said in an email.
“Ultimately, we want to measure the properties of galactic centers as well as possible. In this way, we can learn about the history and structure of galaxies, test theories, and find out whether wormholes or “We can infer the existence of very interesting and interesting astronomical objects,” added Stojković, lead author of the book. 2019 survey About virtual structures.