Open the door of parallel world

  I am actually not these, nor in this world. In the parallel world, I am all these, even more.
  I am not crazy, nor am I telling science fiction stories. According to the multiworld interpretation, these are the facts.
  Multi-world interpretation is an interpretation of quantum mechanics. It believes that there are many parallel worlds in the same time and space as our world. The multi-world interpretation also believes that every choice I make in this world will produce multiple parallel worlds: each world corresponds to one of the choices I made. It can be said that in fact all possible things have already happened or will happen, but they are in different parallel worlds.
  What impact will the existence of the parallel world have on our lives? Should we worry about this? One strategy is that we can completely ignore the other worlds. After all, the multi-world interpretation has told us that it is impossible for you to communicate with another world, let alone encounter you in another world. However, if the multi-world interpretation is correct, it will indeed produce many novel inferences, which can be said to change our worldview.
  Subvert your worldview
  you have multiple identities
  possibility of everything that happens in the universe there are numerous species, then it means that the universe has an infinite number of parallel worlds, each world tells a different story about the universe. Based on this, we can re-examine human nature. For example, in a certain world, you may never kill anyone, but you may have this idea; in another world, you actually did it; and in another world, you will be the scariest place there Murderer; on the contrary, in another world, you are working hard to bring peace there.
  You are no different with others,
  though you are a terrorist murderer in one world, but do not worry, in fact, anyone will be so in a world. Although everyone is different in this world, if you consider other worlds, it is clear that everyone will be very similar.
  You can live forever
  First, let’s talk about a thought experiment called “quantum suicide”. This experiment only needs to replace the cat in Schrödinger’s cat experiment with an experimenter. According to the classical quantum interpretation, in every experiment, the experimenter has a half probability of surviving, so after any experiment, the probability of the experimenter’s survival will be lower and lower. However, according to the multi-world interpretation, no matter how many experiments are passed, there will always be a world in which the experimenter will never die and the survival probability will always be 100%. This situation is called “quantum immortality”.
  Technically speaking, everyone can live forever in a certain world. Although the traditional view is that we live in the world for a period of time, then rot underground and return to various molecules. But parallel worlds have opened one door after another for life: even if you die in this world, you are still alive in another world, and there can be infinitely many worlds in the universe, so You can exist in this universe forever, unless the entire universe is destroyed.
  We’re just a projection
  British American physicist David Bohm has proposed holographic universe theory, we believe that an independent entity directly visible to the naked eye three-dimensional material world, is actually a projection of higher dimensions as a whole, we can not due Understand the wholeness of higher dimensions, and mistakenly think that what we see are independent individuals. This view is actually similar to the multi-world interpretation. The multi-world interpretation believes that the entire universe is a whole composed of an infinite number of worlds, and the world we observe is only a small part of the reality in this universe, and the others are hidden from view. So, we are just a shadow cast by the entire universe.
  Reality to us to create
  even though we only live in a world in which, although we are involved in the process of creating this world. Every quantum experiment, every choice, will determine the direction of our world. The world we live in has a unique past, and we may not be able to change it, but in the future it will evolve into multiple worlds, and part of the decision is in our hands. Want to live in a better world? Then make your own major choice.
  Maybe nothing is true
  There are countless worlds in the universe, and every possibility is real. But since everything is true, it can also be said that nothing is true. Our world is just one of countless dreams. Although it seems that this view has negative elements, it may be the case.
  These are all our inferences about the parallel world, but you have to understand that in the future there will be hundreds of millions of you considering these inferences from different angles, which will give you hundreds of millions of thoughts, and one of them will eventually become You in this world.
  Why have a parallel world
  intricate Schrodinger’s Cat
  parallel world is so mysterious, how many scientific basis of it? Or is it just a scientist’s random thinking? Quantum theory gives a clear answer to this: The parallel world is based on scientific deduction, although we cannot confirm it through observations.
  In the quantum world, microscopic particles can be in multiple states at the same time. This state is called a superposition state, and physicists can use a mathematical tool called a wave function to describe it. But in reality, when we detect microscopic particles, the superposition of the particles disappears automatically, and only one result is finally obtained. Why? Traditional quantum theory believes that once an observer observes a particle, the wave function will “collapse” and become one of the states randomly. This traditional view is the Copenhagen interpretation, which was mainly put forward by the Danish physicist Niels Bohr and the German physicist Werner Heisenberg in their joint research in Copenhagen in 1927.
  Austrian physicist Erwin Schrödinger did not agree with the Copenhagen interpretation, so he gave a very famous thought experiment-Schrödinger’s cat. If you put a cat, radioactive nucleus, and a glass bottle containing highly toxic gas in a closed box, when the detector in the box detects decay particles, it will break a glass bottle with highly toxic gas. Would kill the cat. Radioactive nuclei have a half probability of decay, but if no observations are made, the decay particles are in a superposition state of both existence and nonexistence. In this way, after the experiment is carried out for a period of time, the cat will be in the superposition state of both alive and dead at the same time, unless you open the box to observe the internal situation, so that measuring the state of the cat will make the superposition state of the cat alive and dead mutate into the only state , Which is the collapse of the wave function.
  The biggest question of Copenhagen’s interpretation: Why does the measurement cause the wave function to collapse? How does the wave function collapse? These questions are always difficult to answer and become the biggest weakness of Copenhagen’s interpretation.
  So the multi-world interpretation came. It was first proposed by American physicist Hugh Everett in 1957. Multi-world interpretation believes that every measurement result has already “occurred”, but is in a different “world” or “universe”. In this way, the wave function does not collapse at all, and the state of the particle is still a superposition state. For example, for Schrödinger’s cat, Everett believes that after opening the box, the universe split into two worlds: in one world the cat is alive, and in the other world the cat is dead. Once separated, these worlds go their separate ways, and there is no intersection between them.

  a quantum measurement can produce both worlds, if we regularly carry out quantum measurements, are we going to produce an infinite number of different worlds? In order to explain the quantum measurement problem, as to this? This question may seem confusing, but it is not so marginal.
  To understand why the multi-world interpretation is like this, let’s compare classical physics and quantum physics. In classical mechanics, objects can have a definite state and can be directly observed, but this is not the case in the quantum world. For example, a microscopic particle, in which there are two spin directions: upward and downward. If it is classical mechanics, then the possible states of the particle are:
  ”spin up” or “spin down”
  . For quantum mechanics, the particle is in a superposition of all states at the same time. We can superpose this The state is expressed in the following form:
  ”spin up” + “spin down”.
  Among them, the above “+” means to superimpose the two states together.
  In order to describe the measurement process of this superposition state, we have to add an observer. But this does not mean that we need a “conscious” observer, we can only need an instrument that can detect the microscopic world. The observer can be a living person or just a video recorder. To avoid confusion, we just call it an “instrument.”
  In most cases, the state of the instrument and the particles are independent of each other. If the instrument is taken into consideration, there are two situations. According to the traditional view, when an instrument observes a particle, the quantum state will collapse into one of two possible states: spin up or spin down, which is the case:
  (“spin up”; instrument says “Face up”) or (“spin down”; the instrument says “face down”).
  So, why not change “or” to “+”? Therefore, when the instrument observes particles, the final situation is this:
  (“spin up”; instrument says “up”) + (“spin down”; instrument says “down”).
  This situation means that the instrument enters the superposition state together with the particle, and the original wave function of the particle will not collapse. The instrument has entered a superposition state, indicating that it is in a variety of states, but we only get one of the observation results in reality, and never found that the instrument can display multiple observation results at the same time. Why is this?
  Because in reality, besides this particle and instrument, there are other things: here are other things on the earth, and the outside of the earth is a vast space. These things—they are called “environments” in combination—also have a quantum state. The photons and air molecules in the environment will constantly collide with the instrument. In this way, we cannot isolate the instrument from the environment, but should take the environment into consideration. Thus, the superposition state of the system can be written in the following form:
  (“spin up”; instrument says “up”; environment 1) + (“spin down”; instrument says “down”; environment 2).
  It can be seen that the environment split into two independent environments. This means that when we make quantum measurements, the wave function has never collapsed, but there will be two worlds that have nothing to do with each other in the universe.
  In the above discussion, we only used the basic laws of quantum mechanics, so quantum mechanics itself contains the idea of ​​parallel worlds, whether you like it or not.
  Interactive parallel world
  a lot and limited parallel world
  I said before, Everett’s many-worlds interpretation is the wave function as an important part of the theory, and the predicted and experimental results perfectly match. But what exactly is the wave function? Is reality real, or is it just a calculation tool we invented? What is the reality?
  To solve this confusion, physicist Howard Wiseman from Griffith University in Australia and his colleagues recently found a way. Simply put, their method is to remove the concept of wave function and replace it with a large but limited parallel world. They claim that our world shares the same space with a large number of other worlds, and that Newton’s classical laws of physics are followed in each world. The particles in our world can produce a subtle force with the particles in all other worlds. What we think of as weird phenomena in the quantum world is the result of these worlds colliding with each other. If the interaction between these worlds does not exist, or there is only one world, then all quantum phenomena will disappear and Newtonian physics will rule everything.
  This theory is called the interactive parallel world theory. In addition to the absence of the concept of wave function, this theory differs from the multi-world interpretation in that: the number of parallel worlds is limited; parallel worlds have always existed even before quantum measurement; parallel worlds can interact with each other through corresponding particles. effect.
  In order to prove that their theory is indeed feasible, Wiseman and his colleagues used their interactive parallel world theory to explain some quantum phenomena. They chose a typical experiment, the double-slit interference experiment. In this experiment, photons are emitted from the emitter one by one, pass through two parallel slits, and reach the photosensitive plate behind. If the photon is just a particle, then you will see two spots on the photosensitive plate corresponding to the slits. But this is not the case. The light and dark interference fringes appear on the photosensitive plate. How do interference fringes appear? It is generally believed that photons are also a kind of waves, which can pass through two slits at the same time, and the two waves formed after passing through will interfere with each other. This experiment shows that photons have wave-particle duality.
  According to the interactive parallel world theory, each photon interacts with the “ghost” photon in other worlds, which makes the photon path of our world produce specific changes. Wiseman and his colleagues found that only 41 worlds are needed to produce the same interference fringes as the experiment.
  Maybe you can really talk to another world
  They said that the interaction between multiple worlds may explain many unsolved mysteries, such as gravity. For a long time, among the four basic forces of gravity, electromagnetic force, strong force and weak force, gravity and the other three forces cannot be unified. This is one of the biggest problems in modern theoretical physics. If gravity comes from the force of other worlds on our world, it is normal that it cannot be combined with the other three forces.
  In addition, the prediction of quantum phenomena made by Schrodinger’s equation is equivalent to an infinite number of multiple worlds. If the number of the world is finite, then the Schrodinger equation is only an approximation. Through careful observation and analysis of experiments, we may also determine how many worlds exist.
  However, this theory is still in its infancy and needs a lot of theoretical support. Whether it can completely replace the wave function, physicists are still uncertain. But if this theory is correct, then comes an exciting possibility: we can find evidence of the existence of other worlds through experiments, and even communicate with other worlds indirectly. Maybe one day, you will really talk to you in another world.