Why are black holes the scariest thing in the universe?

 According to foreign media(2021 hermes) reports, nothing in the universe is more terrifying than a black hole.

　　 Black hole is a region in the universe with extremely strong gravitational force. No matter can escape from it. Recently, the topic of black holes is also frequently seen in newspapers. In 2020, half of the Nobel Prize in Physics was awarded to Roger Penrose because his mathematical work proved that black holes are the inevitable result of Einstein's theory of gravity. Andrea Götz and Reinhard Henzell shared the other half of the Nobel Prize in Physics. The reason for the award was that they discovered that the center of the Milky Way is a huge black hole.

　　 Black holes are particularly terrible for three reasons. If you fall into a black hole formed when a star dies, you will be torn apart; in the same way, the supermassive black holes at the center of all galaxies seem to be hungry forever; and the laws of physics no longer apply in black holes.

　　 Chris Impe has been studying black holes for more than 30 years, especially focusing on the supermassive black holes lurking in the center of galaxies. In most cases, these black holes are inactive. However, once active, they will devour stars and cloud gas, and the area near the black hole will be more dazzling than the entire galaxy in which the area is located. Galaxies with active black holes are called quasars. Although we have acquired a lot of information about black holes in the past few decades, there are still many mysteries waiting for us to solve.

　　 died in a black hole

　　 When a massive star dies, a black hole may form. After a star's nuclear fuel is exhausted, its core collapses into extremely dense matter, more than a hundred times the density of an atomic nucleus. With such a high density, protons, neutrons and electrons are no longer discrete particles. Because the black hole is pitch black, we can only find it when it orbits a normal star. The properties of a normal star allow astronomers to infer the properties of the star's dark companion, the black hole. The first black hole discovered was Cygnus X-1, the brightest X-ray source in the constellation Cygnus.

　　A black hole is a tomb of matter; no matter, even light, can escape from a black hole. Anyone falling into a black hole waiting for his fate will be a very painful "spaghettiization" process. This is an interesting metaphor put forward by Stephen Hawking in A Brief History of Time. In the process of spaghettiization, the huge gravity of the black hole will stretch you very long, separating your bones, muscles, bones and even molecules one by one. The words engraved on the gate of hell in Dante's poem "The Divine Comedy"-"He who enters this gate has broken hope", depicts this process very vividly.

　　 Hungry monsters in every galaxy(hermes outlet online)

　　In the past 30 years, people have observed with the Hubble Space Telescope that there is a black hole in the center of all galaxies. The larger the galaxy, the larger the black hole.

　　Nature knows how to create black holes of vastly different masses, from stellar remains that are several times the mass of the sun to monsters that are tens of billions of suns. The gap between this is like the gap between an apple and the pyramids of Giza.

　　 Just last year, astronomers released the first ever black hole photo and its event horizon. This is a giant with a mass of 7 billion solar masses at the center of the M87 elliptical galaxy.

　　 It is a thousand times larger than the black hole in the center of our galaxy. These black holes are pitch black most of the time, but when their gravity attracts nearby stars and clouds, they will explode violently and emit a lot of radiation. The danger of massive black holes lies in two aspects. First, if you get too close, the huge gravity will draw you into the black hole. Second, if they are in the active quasar phase, you may be scorched by high-energy radiation.

　　 How bright are quasars? Imagine you hovering over a big city like Los Angeles at night. The lights of cars, houses, and streets are the stars in the galaxy. By analogy, an active black hole is like a 1-inch-diameter light source in downtown Los Angeles, but it illuminates the entire city. Quasars are the most dazzling celestial bodies in the universe.

　　 strange supermassive black hole

　　So far, the mass of the largest black hole discovered by mankind is 40 billion times the mass of the sun, or 20 times the diameter of the solar system. The orbital period of an extrasolar planet is 250 years, but this supermassive body can rotate once every three months. The moving speed of its outer edge is half the speed of light. Like all black holes, super-large black holes are hidden behind the event horizon, making it impossible for people to know their true colors. The center of the black hole is a singularity, that is, a point of infinite density. We cannot understand the inside of a black hole because the laws of physics no longer apply here. Time freezes at the event horizon, and gravity becomes infinite at the singularity.

　　 But the good news is that if you fall into a supermassive black hole, you may be lucky enough to survive. Compared with smaller black holes, although their gravity is stronger, their tension is weaker, so they will not kill you. The bad news is that the event horizon is like the edge of an abyss. Once you enter the event horizon, it is impossible to think of it again. So, after you fall into it, even if you are not dead, you can't escape, let alone tell others about your experience.

　　 According to Stephen Hawking, black holes are slowly disappearing. In the distant future of the universe, after all stars have died, and all galaxies have become more and more dispersed under the action of accelerated expansion of the universe, black holes will be the last remaining celestial bodies in the universe.

　　The largest black hole may take a long time to disappear. And this is a long time, close to eternity. In other words, the most terrifying celestial bodies in the universe exist almost eternally.