Schrodinger's cat, life and death, and its true meaning

　　Schrodinger's cat is one of the most famous thought experiments in all sciences. It is the source of countless jokes, T-shirts and pseudo-intellectual conversations.

　　The principle of the experiment is that if a cat is put into a box with a well-designed quantum booby trap, then when we open the box, the booby trap will either be activated and kill the cat, or it will not be activated at all.

　　Quantum physics believes that when we don't look at this cat, it should be in a state of superposition, just like other parts of the quantum system. In other words, before we saw it, the cat was both alive and dead, zombie cat.

　　Incredible, but Schrodinger didn't mean it at all.

　　The quantum physicist Erwin Schrodinger designed this thought experiment to show that the Copenhagen interpretation of quantum mechanics (that is, the mainstream interpretation) must be wrong.

　　He pointed out that we can't think that a cat is both alive and dead at the same time, but if Copenhagen explains that this is the case, then it must be wrong.

　　Einstein didn't quite agree with many points of view of quantum mechanics, but he also agreed and wrote to Irwin. Besides Laue, you are the only contemporary physicist who sees that as long as you are honest, you can't bypass the realistic hypothesis.

　　Most of them don't realize what kind of adventure game they are playing in reality-reality is independent of what is determined by experiments.

　　However, your "radioactive atom+amplifier+gunpowder+cat in a box" system most elegantly refutes their explanation. In this system, psi function includes both living cats and cats blown to pieces. No one really doubts that the existence of cats has nothing to do with observing behavior.

　　Later, Schrodinger tried to make a purely wave-based understanding of quantum mechanics, but this understanding was never as popular or successful as the Copenhagen understanding, which still dominates today.

　　Of course, there are other ways of understanding. The following are several ways, and what happened to the poor cat under each way of understanding. Besides these, there are more explanations, but these are the most popular alternatives.

　　A happy cat is neither in quantum superposition nor in a box with traps.

　　Multiple worlds, many people know the concept of multiple universes. In this explanation, cats live in one universe and die in another.

　　The new universe was "created" when a cat was observed. This cat does not have the problem of being alive or dead. This model of the universe can be seen in popular works.

　　The target crashes. These theories hold that the system will crash long before you open the box, either because of the passage of time or other simple events.

　　Therefore, before you open the box, the cat's life and death status has been determined. However, it also leaves us with the possibility that the cat will live or die at least for a short time, but not for too long.

　　In theory, these are all very good. Has anyone done any experiments?

　　Yes, but not on cats. In order to achieve these goals, we put some relatively large objects in a superposition state. However, these States do not seem to last long.

　　We haven't even reached the point where bacteria are in a cat state. It seems that no one has done the experiment yet, or that no one will do it for some time.

　　Schrodinger's cat is one of the most famous thought experiments in science. Most people know it, but few people can understand it. Although its original intention is only a simple criticism, it has evolved into a key test to judge how the understanding of quantum mechanics works and whether this explanation is feasible.

　　Is the cat alive? Is he dead? Are they both? How do we know? How is that possible?

　　If possible, don't always tell yourself, but how can it be like that? Because you will "fall into the sewer" and fall into a river where no one can escape. No one knows how this happened.

　　This is still a controversial topic in physics and philosophy. Maybe someone will come up with a new explanation, and finally let the cat rest in peace, or let it live outside the box, or both.