If we accidentally fall into a black hole, we won't cross it!
Black holes are one of the most mysterious things in this world. What exactly is a black hole, and what is the meaning of its existence. In modern general relativity, a black hole is a celestial body that exists in space, but a black hole is an unobservable, invisible object. A black hole is a celestial body with a curvature so large that light cannot escape from its event horizon. The gravitational pull of a black hole is so strong that the speed of light cannot escape the gravitational pull of the black hole, so we humans cannot observe the black hole.
While we can't directly observe black holes, clever humans have inferred their location and mass through the trajectories of stars and other stars, as well as the surrounding space-time affected by black holes.
And black holes are divided into three categories by mass: stellar-mass black holes, intermediate-mass black holes, and supermassive black holes. As can be seen from the names of the classifications, black holes are particularly massive, and even the smallest black holes have a mass of several times or even hundreds of times that of the Sun.
Why do black holes have such a large mass and gravitational pull? According to Einstein's theory of general relativity, the final stage of a star's death becomes a black hole, and the core of a star eventually collapses into an infinitely small, infinitely dense point. A simple metaphor is like a ball of infinite density that falls on a mattress and is twisted and collapsed around the ball. Then as long as all the matter that enters the boundary of the black hole, even the light, will be sucked in and there is no way to escape. So we can only see black holes, and by the way, black holes don't absorb things like vacuum cleaners. Only when matter or light enters the boundary of the black hole, it is absorbed by the black hole, which is also known as the event horizon.
When we learn about black holes, what happens to us if we fall into them. When we get close to the event horizon, from the outside we become extremely slowly moving because the time space around the black hole is distorted. At a certain moment, you look like you've frozen in time, then slowly turned red and finally disappeared. It's also possible that once we cross the event horizon, it's like walking into a very narrow alley, with no way to turn back, only one direction, and nothing behind us. Then a force squeezes you continuously, and finally the cells of your body are squeezed apart and turned into a stream of heat like atoms. All of this is conjecture, and perhaps only if it is actually dropped into it will we know what it will become. But either way, you probably don't want to go inside a black hole. Well, this issue of sharing is here, I am Xiao Zhou, pay attention to me to take you to learn more knowledge.