For many years the minds of science fiction writers have been tormented by the thought of how to explain to the reader or viewer that parallel worlds exist. You also need to explain how it all works, why there is life and why it is similar or not similar to ours. All this reasoning on the topic of parallel universes rarely leads to any specific answers. If it were that simple, the best physicists would not puzzle over quantum states and how electrons can exist in two places at the same time. While they continue to do this and exchange only theories and reasoning, without giving specific facts and proofs, you and I have an excellent opportunity to speculate ourselves on the topic of parallel worlds that excite the minds. After all, scientists are no more factual than ours.
What are parallel worlds
There is no clear definition of this concept, since according to different theories, some mean one thing by this, while others talk about something completely different. If we try to somehow generalize all theories, then parallel worlds are other realities, in which we live, and possibly someone else.
In any case, this is, so to speak, another world, into which we can hardly get. However, one of the theories says that these worlds periodically collide and exert a gravitational effect on each other. It even leaves its mark on the relic radiation. However, let's talk about this below.
There are various theories about parallel worlds. Some explain this phenomenon from the point of view of religion, others from the point of view of magic, and still others from the point of view of physics. It is about the physical explanation that we will talk today.
Of course, parallel worlds may look like this, but only in movies.
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How to prove the existence of parallel worlds
One of the theories says that parallel worlds exist. Yes, it's that simple. According to this theory, first proposed by the American physicist Hugh Everett, there is at least one world parallel to ours.
He called his reasoning the theory of a probable set of worlds. It draws on the claims of scientists from the field of quantum physics. According to these statements, an electron can exist in two places in space at the same time. This property is called a superposition of two states.
An interesting feature of this superposition is that as soon as we try to understand where this electron is, for example, we influence it, it will immediately move. Moreover, although they are a copy of each other, if we try to determine their position, it turns out that we will see only one. In fact, all this looks more like some kind of scam, they say you don't see, but it exists, but this is part of quantum physics. That part of quantum physics, which has a number of assumptions and basic rules, without which it is simply impossible to explain everything that happens in the world. Such rules apply to many phenomena, which is why they are the laws of quantum physics. We can only believe in them.
Hugh Everett's theory takes this behavior of quantum particles as the basis for proving the existence of parallel worlds. That is, if we try to identify an electron in space and understand where it is, then we ourselves will become a quantum object and find ourselves in two states. In one of them, one electron will be available to us, and in the second, another. That is, these are parallel worlds based on the superposition of states.
Hugh Everett.
So it is with the famous Schrödinger's cat, which, according to a hypothetical experiment, was immersed in a box of poison and he was alive and dead at the same time. It's just that when we opened the box and saw the poor cat in one state, in a parallel world someone saw him in another state. This is another important rule of parallel worlds - opposite events take place in them.
Moreover, the number of such worlds can be more than two. It is limited only by the number of probable outcomes of any event. But to say that events take place in another universe, which is simply connected with ours at the quantum level, is not necessary. According to the theory, there is only one Universe, and the given examples of parallel worlds are only layers of this single Universe, which are formed every time an event occurs that has several different outcomes.
The fact that we do not create a separate universe explains why we cannot get into parallel worlds. We cannot move to another layer. There are other us who make opposite decisions and go our own way. For them, our world is parallel.
Are you ready to visit parallel worlds? No, this is not possible.
In reality, such a theory simply links quantum concepts of superpositions with the real world and tries to explain the existence of parallel worlds on the basis of this.
Parallel worlds from a string theory perspective
There are two main theories in the world to explain everything - general relativity and quantum field theory. The first explains the interaction in the macrocosm, and the second - in the microcosm. The problem is that if we imagine both worlds on the same scale, that is, simply imagine our world, then both these theories contradict each other.
As soon as not trying to visualize string theory, but it turns out not very well.
In order to explain everything in the world with one general theory, scientists in the 1970s actively hooked on string theory. The strings were something arbitrary, which was supposed to explain the physical characteristics of the smallest particles and their interaction with other particles at any scale, but later it turned out that this theory does not always work and something else must be looked for.
By itself, this does not prove the existence of parallel worlds, but in 1998 the cosmologist Max Tegmar put forward a theory that gives reason to think about the existence of other Universes with other physical constants different from ours.
Many scientists were hooked on this theory and suggested that these Universes are our parallel worlds. In theory, you can even get to them, especially if you go through a black hole, which, in theory, connects our universe with others.
In response to those who disprove the existence of other universes, proponents of the theory argue that our understanding of the universes is reduced only to what we see. That is, to the space around us that corresponds to the distance covered by light in 13.8 billion years. This is how much has passed since the Big Bang and we see only those stars, galaxies and worlds, the light from which has managed to reach us. Perhaps, in another billion years, light from other universes will reach us
Universes after the Big Bang can exist as you like, anywhere.
Many scientists also claim that these Universes are our parallel worlds. Some even rely on changes in the relic radiation, arguing that changes in its behavior are a consequence of the collision of universes, which seem to float in a large ocean and periodically collide with each other.
Is our world the only one
Most scientists agree that it is at least silly to consider our world to be the only one. And it is much easier to assume that there are many worlds than to claim that there is only one.
Moreover, quantum physics and the laws of interaction of everything in the world constantly bring even more confusion into the arguments and disputes of physicists. We can only believe or not believe in the reasoning of scientists. We still cannot understand all the secrets of the universe and how everything works. Scientists also have not been given this and will not be given it for many more years. But they devote their lives to this and are a couple of steps closer to the solution than we are. Here are just a few hundred kilometers before this solution. And even more before understanding it.
Artem Sutyagin