In these universes, there are universes born under the same conditions as us, there may be planets with the same history as the planet where human beings live, and there may be people exactly like human beings.
At the same time, in these different universes, the development of things will have different results: species that are extinct in our universe may evolve and live endlessly in another universe.
In 1950s, when some physicists observed quantum, they found that each quantum state was different. Because all matter in space is made up of quanta.
So these scientists speculate that because each quantum has a different state, it is possible that there is not just one universe, but several similar universes. The concept of parallel universe benefits from the scientific discovery of modern quantum mechanics.
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The development course of parallel universe
In the 5th century BC, democritus put forward the concept of "countless worlds", believing that "countless worlds" were formed by atoms through their own movement. He said: "Atoms move freely in the void, but because of their sharp and disorderly movement, they collide with each other. When they touch each other, they collude with each other because of their various shapes, thus forming the world and its things, or forming countless worlds."
In 1 century BC, Lucretius pointed out that besides our "visible world", there are "other worlds" inhabited by "other races of human beings and beasts".
In the 4th century BC, Epicurus expressed the idea of world pluralism: "There are infinite kinds of worlds, some of which are like ours and some are not." "In all the worlds, there are animals, plants and other things that we see in this world."
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