This kind of idea appears in many science fiction novels and movies, which is the famous "brain in a vat" idea. So, can this vision be realized in reality?
First of all, we need to understand the specific structure of the human brain, mainly the structure of the nervous system.
The nervous system of the human brain is quite complex, composed of nerve fibers that transmit various nerve signals to various organs throughout the body. Of course, every organ of the body can also be transmitted to our brain and spinal cord through neural tissue.
In other words, the brain and spinal cord are the centers of the human nervous system, and everything we perceive around us comes from the brain and spinal cord.
As a simple example, while chopping vegetables, you accidentally cut your finger and you will be in great pain. Where does this pain come from?
It is the nerves near the finger wound that transmit nerve signals to the brain, which makes you feel pain. There are also many people who often experience toothache, and many times the dentist will first remove the nerve near the broken tooth to temporarily relieve the toothache before further treatment. Without nerves near the teeth, there would be no signal to the brain, and of course no pain would be felt.
There are even more special giraffes. Because the giraffe's nervous system transmits very slowly, when a giraffe is injured, it does not feel pain immediately, and it can even take up to a week to feel the pain, because it takes up to a week or so for the nervous system to travel from the giraffe's feet to the brain.
From the way the brain and nervous system work, it is clear that if the human brain is not working, the brain dies, which means the death of a person.
In other words, the criterion for judging whether a person is dead is not by heartbeat, breathing, but by whether the brain is dead. To put it bluntly, brain death means the real death of a person!
Knowing this, I moved on.
When the nervous system transmits various signals, it usually does so in neurons, which transmit electrical signals and chemical signals between two neurons.
Hence the famous "Brain in a Vat" thought experiment, about an evil scientist who had the whimsical idea to remove the person's brain during surgery on a patient and put it in a pre-prepared nutrient solution that would ensure the proper functioning of the brain.
Then the evil scientists connect a computer to the nerve endings of the brain, and continuously input various electrical signals to the brain, simulating various real-life scenarios, so that the brain feels that everything is normal. So is this person still alive? If so, is he living in a virtual world?
Theoretically, all of these simulations are possible, because as mentioned above, all of our perception of the real world is essentially electrical signals. Some people may question: slapping yourself in the face, if you feel pain, it is not a virtual world. In fact, this kind of questioning is easy to explain, pain is also a certain electrical signal transmitted to the brain to read, of course, it can also be simulated.
The famous science fiction movie "The Matrix" is such a storyline, which cultivates many people in a nutrient solution, and then connects the computer system with the brain, constantly stimulates the brain with various electrical signals, and fictionalizes a near-perfect virtual world, in which everything perceived by everyone is no different from what we perceive in reality, and every day we will get up at one o'clock, commute to work, eat, etc., and it feels like the real world.
But wait. Why do we always think that the world we live in must be real? Since the "brain in a vat" is theoretically feasible, and this experiment can simulate everything in reality, isn't the so-called real world a "brain in a vat"?
Sadly, we can never be sure if we are living in a "brain in a vat" world, because we cannot be separated from the world we live in, and we cannot look at our situation from the perspective of God.
To be honest, the "brain in a vat" experiment is relatively easier for us to understand and accept, after all, there is a physical brain. What many people can't accept is that the reality may be even more "terrifying": there is not even the brain as an entity, we live in a virtual world, and everything we see, including ourselves, is essentially a virtual program composed of the numbers 0 and 1!
Just like the computer game The Sims, our world is a virtual program, and the world we live in is run according to a set program.
What's even more terrifying is that, like the "brain in a jar", we can never prove whether the world is virtual or not.
The deeper conclusion is that the so-called virtual and real are actually relative, there is no absolute real and virtual, as long as we think it is real, it is real.
Maybe there really is some super civilization in a higher dimension that simulates our world, but so what?
In the eyes of super civilizations, the world of human beings is indeed virtual, but for us human beings, the world is real. Just like the computer games we play every day, the characters in them feel that their world is real, and it is impossible for them to prove that the world they live in is virtual.
Humans design computer games for entertainment, so if our world is really simulated by super civilizations, what is their purpose?
It's hard to guess that this is a difference in different dimensions, a chasm that humanity can never overcome. Maybe the purpose of the super civilization to design the virtual world is to experience different lives, they can enter our virtual world in person, experience a variety of different lives, maybe at this moment, someone around you is from the super civilization, but you can't find it anyway.
Just like human beings today, one day in the future, with the continuous development of human technology, human beings can also allow themselves to enter the virtual computer world and experience the rich world of computer games.
Or perhaps the purpose of the high-dimensional super civilization to simulate our world is to test the development law of intelligent civilization, and to avoid these problems and risks in advance by observing the various problems and risks that arise in the development process of the virtual world, so that you can avoid detours.
As for what the truth is, it is unknown.
But whatever it is, the most important thing is that in the eyes of us humans ourselves, the world is real, and that's enough!