[박종진의 과학 이야기] Singularity

We say something is unusual when it is neither normal nor normal. A black hole is a celestial body that was created when a star larger than our sun collapsed at the end of its life, unable to overcome its own gravity It cannot be explained using the physics that we have developed it today. To put it simply, it refers to a celestial body that has no size but infinite density, and is still a common theme in science fiction novels and movies.

Schwarzschild, a German physicist who worked at the same time as Einstein, thought that the speed at which an object with decreasing mass becomes equal to the speed of light leaves surface at some point. Stars like the sun have a stable period when the radiation pressure that threatens to explode as it emits light through a nuclear fusion reaction and the gravitational pull within the star is balanced, but when the hydrogen substance is reduced, it collapses due to gravity. It will be the final form of the celestial body imagined by Schwarzschild: a black hole. This is why Schwarzschild is known as the pioneer of black holes.

Later, a physicist called John Wheeler used the somewhat longer phrase ‘a thing that collapsed entirely due to gravity’, and during a lecture, a member of the audience suggested that a Black Hole should simply be on, and so it was named so. However, people who liked to talk about black were worried that it sounded like a sexual expression, but because Wheeler was an honest and solemn Jewish scientist, he was given the official name Black Hole . Wheeler was also the first scientist to use the word wormhole.

The radius of a black hole is determined by its own mass, called the Schwarzschild radius. Once you reach the singularity of a black hole, gravity is so close to infinite that even light cannot come back. So the boundary line is called the event horizon. Modern physics assumes that the Big Bang universe, which began 13.8 billion years ago, began from such a unique unity.

Although humanity has gone through classical physics from Newton to Einstein and even quantum mechanics, we still cannot explain the uniqueness of black holes with our physics. According to observations so far, the black hole rotates very quickly. However, according to the laws of the universe, its rotational speed cannot exceed the speed of light. As the medium rotates at a speed similar to light, a hole is created in space, hence the name black hole, meaning an invisible hole. The edge of the hole is the event horizon, beyond which nothing, including light, can return. That’s the only point.

The mainstream of modern cosmology is Big Bang cosmology. The universe, which began 13.8 billion years ago when there was no time or space, has expanded enormously to the present day. That is the singularity. We render something unknown by the prefixes x (X-ray image, the x term in an equation), dark (dark matter, dark energy), and black (black hole). Black holes, whose outlines are gradually revealed as a result of the development of science, will soon come up with a formula that explains the singularity.

Now is the time of electric energy. However, just 300 years ago, mankind could not even dream of using electricity as a source of power. Likewise, the day will soon come when the secret of violence will be revealed. (author)

Jongjin Park