black holes are the most strange known celestial bodies in the universe. They are usually the product of massive celestial bodies collapsed sharply inward after death, with great density and mass.
But theoretically, any object can become a black hole, provided that the object is compressed small enough. In other words, any object has its own " Schwarzsie Radius ". When the object is compressed into a space with the size of Schwarzsie radius, it will collapse into a black hole.
For example, Everest , when it is compressed into a range of 1 nanometer, it will become a black hole. The same is true for our Earth. The Earth is compressed to the size of peanuts and will also become a black hole. The larger the mass of an object, the larger the Schwarzsai radius.
So, what kind of experience will you have if you accidentally fall into a black hole?
has an effect called " gravitational lens effect ". In layman's terms, gravity will bend space-time, and light moves in curved space-time. The most common example is that the stars we see are not actually at the location we see, because the light emitted by the stars is curved.
Because the black hole has huge gravity, the bending of light has reached its limit. photons will pull the huge gravity of the black hole and rotate around the black hole.
So in the process of falling into a black hole, you can theoretically see the back of your head. Because the light reflected in the back of your head rotates around the black hole and enters your eyes.
But for observers outside the black hole, everything becomes very different.
Since gravity can also slow down time, for external observers, they will not see you quickly being swallowed by the black hole, but you fall into the black hole slower and slower. In the end, when you are infinitely close to the event horizon of the black hole, you are completely still.
Because the event horizon of a black hole is the dividing line of time and space. Once it passes through the event horizon of a black hole, there is no concept of time. For external observers, your time stops, and is still in the event horizon, just like a photo.
But for you, you will not stay in the event horizon, but will cross the event horizon and fall toward the center of the black hole, which is the direction of singularity .
All matter in black holes is concentrated on infinitely small singularities. In theory, the gravity of the singularities is infinite, so when you get closer to the singularities, they will be completely torn apart very quickly. And if your footsteps get closer to the singularity first, the gravity felt by the footsteps will be much larger than the head, and you will be pulled longer and longer by the powerful gravity of the black hole, just like a noodles.
And when you reach the singularity, we don’t know what will happen. Because the singularity itself is a existence separated from the modern physics system, and it is completely separated from the four-dimensional space-time where we are. To put it bluntly, it is another world that we cannot understand for the time being!
Scientists believe that the singularity of black holes, especially black holes, is likely to hide the ultimate mystery of the universe, such as the portal that moves instantly, and even the mystery of high-dimensionality.
