Part of our dreams is made up of bits and pieces of memories we see. We have seen some scenes, and then when we sleep at night, our brains will fall into a rest, but our subconscious will move. This activity is passive, not our active thinking, so it combines some gloomy memories scattered outside people's long-term memory, and then we have a dream. We feel very real in some scenes, but we don't know why or how we came here.
It can be said that the content of dreaming is influenced by people's brain wave activities, but now people have not found a way to control the content of dreams, and there are corresponding expressions in some movies, but people can't do it yet, because dreaming and active thinking are two opposite processes. Once people realize that they are in a dream, our brain will change from passive thinking to active thinking, and the dream will wake up, so we can't control the content of the dream. Some scientists keep telling themselves that they are dreaming through hints before going to bed, and then they can know that they are dreaming to some extent when they are dreaming, but they can't control their dreams.
In fact, people have never heard of the study of dreams. There were books about Duke Zhou in ancient times, and now some people speculate boldly. Is it possible that when we dream, we realize another space? They are experiencing different lives and even talking about parallel worlds. These are just guesses, so we are just exploring and there is no valid conclusion. After all, everything has to have an initial stage. It may be hundreds of years before we can understand what dreams are.