How are galaxies formed in the universe?

To understand how galaxies are formed, we need to go back to the origin of the universe. At that time, the universe was full of gas clouds left by the Big Bang, and there were thick interstellar gases in some places, thus forming tens of millions of stars. Primitive stars are mostly supermassive stars. They are very hot and burn quickly. After the explosion, they produced a large number of black holes.

Gravity pulls many black holes together, and in the early universe, they merged with each other to form a bigger black hole. Black holes have been growing for hundreds of millions of years, which is called supermassive black holes. The gravitational range of these super black holes can even reach millions of light years. They are constantly dragging more and more interstellar gas into their gravitational range. These gases evolved into hundreds of billions of stars in the process of rotating around the black hole, forming primitive galaxies.

Young galaxies are clusters of stars born in gas. There is a young supermassive black hole at the center of the new galaxy, which grows by swallowing gas. Gas flies into the black hole, but the black hole becomes too saturated, and there is no room for more hot gas to enter. The gas that can't get in is spit out by the black hole and sprayed into space, forming a huge energy flow. No energy flow is 20 times wider than our solar system. They fly all the way through the Milky Way. This supermassive black hole ignited a quasar—

Quasars spew out a lot of interstellar gas from their galaxies, and the quality of gas spewed out every minute is equivalent to 10 Earth. This process will generate huge heat around supermassive black holes. When heated, gas will expand, a bit like wind, but on a large scale. These are the black hole winds, which spread around the black hole at a very strong speed, enough to blow all the gas in the galaxy away from the galaxy.

Black holes suck in gas, quasars eject gas, and eventually there is no excess gas in the galaxy to make stars, and the galaxy stops growing. Therefore, we believe that the final size of a galaxy depends on the size of the supermassive black hole in the center, and the two are closely related. Without gas, quasars gradually shrink and disappear, leaving only a supermassive black hole and many young stars at the center of the galaxy. Our galaxy was like this when it was young, but now, our galaxy has stopped growing and is called a mature galaxy.

Each quasar is the embryonic form of a young galaxy, and there is a supermassive black hole in its center. So it can be said that supermassive black holes and quasars create galaxies and control the whole galaxy.