From the day of human birth, we began to understand the world step by step. In the eyes of the ancients, the world is full of all kinds of miracles and fears. Due to the lack of understanding of all kinds of things in the world, the ancients were full of fear and awe of many natural phenomena. Therefore, there are many myths and legends that believe that these natural phenomena and rules are manipulated by God.
With the continuous development of human civilization, we have entered the palace of science. In the world of science, we begin to have a preliminary and real understanding of the world, all things in the world and all laws. We can find the answer in the ocean of scientific knowledge.
After entering the era of science, human beings have put forward many scientific theories, some of which have been confirmed by us, while others are still in the process of exploration. Five of these scientific theories have been confirmed by scientists, but they are hard for many people to accept. Why? Now let’s first understand one of these five scientific truths that people find hard to accept.
1、 Quantum superposition state, we all know that the world includes macro and micro, the world we can see is the macro world. And behind the macro, there is a micro world that we can’t see. In the last century, scientists discovered the existence of the micro world and put forward the theory of quantum mechanics.
Quantum mechanics is a key to study and explore the micro world. When scientists enter the micro field, they find many miracles that subvert our cognitive theory. Many theories of scientific phenomena in quantum mechanics are completely different from macro theory, and even subvert macro theory, such as superposition state.
Superposition state refers to the state of a quantum system obtained by the normalized linear combination of several quantum states. In short, several states that cannot exist at the same time in the macro world can exist simultaneously in quantum mechanics. For example, up and down, left and right, front and back, life and death and so on, which are completely opposite in the macro world, can only exist at the same time, but in quantum mechanics, they can exist at the same time.
A famous experiment about superposition state is double slit interference experiment. I believe every friend did this experiment when he was in high school. In the experiment, two slits are left with this electron interference fringes. Once we use a special instrument to observe the electron, the interference fringes disappear.
The explanation for this is as follows: when we do not observe, the electron has volatility, so it can disperse and leave stripes; once we observe, a photon hits the electron, and the electron has a definite position, showing particle nature.
It is a very famous experiment that a single photon can interfere with itself, resulting in two interference fringes. Through the experiment, we confirm the authenticity of quantum superposition state. However, this result is hard for many people to accept. It tells us that life and death can exist at the same time in the quantum world, which subverts our cognition.
2、 Quantum tunneling effect and quantum superposition state let us see the magic and mystery of the micro world. In quantum mechanics, there is another phenomenon that is also hard to accept, which is quantum tunneling effect.
In the quantum world, microscopic particles can penetrate or pass through other objects. This magical phenomenon only occurs in quantum mechanics, which is impossible in classical mechanics. Such a scientific theory tells us that theoretically, we can also go through walls.
You know, the material in the macro world is also composed of particles. For example, the human body is composed of a large number of micro particles. If the particles can pass through the object freely, the human body composed of particles should also be able to pass through the wall. This is true in theory, but it has never happened in the macro world.
This result makes many people confused. Since there is tunneling effect in quantum mechanics, particles can pass through objects, why can’t objects composed of particles pass through walls? It is difficult for scientists to give a definite answer to the mystery. What we know is that in the macro world, the probability of an object passing through a wall is not zero.
In other words, theoretically speaking, it is possible for us to successfully cross the wall, but the probability is too small to be negligible. So even if you try to go through the wall a million times, it’s unlikely to succeed. It is only the correct scientific theory in quantum mechanics, but it is not very correct in the real macro world.
3、 Eternal movement, from a normal point of view, there is no eternity in this world. But Newton’s first law tells us that eternal motion exists in theory. We all know that a moving object needs an external force to drive. Only with the injection of external force, can the object have energy to move forward.
The driving force of the car comes from its engine, and the driving force of the basketball’s upward motion comes from our arms. This is the state of motion driven by external force. If a moving object is not driven by external force, according to Newton’s first law, it will move in a straight line at a constant speed forever.
An object without any external force, it will be permanently at rest, will not move. For example, an apple will stay on the table forever without external force.
Newton’s first law allows the existence of this state of eternal static and eternal motion, which is also the theoretical basis for many people to study the perpetual motion machine. But in reality, eternal motion does not exist, because in the macro world, particles can not be absolutely static, they are always in motion.
The static apple, its internal particles are still in constant motion, rather than absolute static. Particles in motion, then the apple composed of particles should also be in motion, but what we see is still on the desktop. This paradox is hard for many people to accept.
4、 The theory of constancy of the speed of light. As we all know, in Einstein’s special theory of relativity, the fastest speed in the universe is the speed of light. If we do not consider the distortion and expansion of the universe itself, the speed of light is definitely the fastest speed of the universe.
Another feature of the speed of light is that it will never change. No matter what kind of movement state and direction, the speed of light will always protect 300000 kilometers per second, no more or no less. In the view of many people, if the speed of our aircraft reaches 30% of the speed of light, then in the process of this speed, a light is emitted from the spacecraft, then the speed of this light should be the speed of light plus 30% of the speed of light.
But in reality, such a thing does not exist. The speed of a light emitted by a 30% speed of light spacecraft is still 300000 kilometers per second, which will not exceed the speed of light. In the past hundred years, scientists have done many experiments on the speed of light, and the final results show that the speed of light is absolutely stellar, rather than changing because of any reference object.
5、 Mpeba effect, in the same mass and same cooling environment, the temperature of the molecules in direct contact with the cooling environment of a slightly higher temperature liquid will drop faster than that of the molecules in direct contact with the cooling environment of a slightly lower temperature. If the cooling environment can always maintain the same cooling capacity (constant temperature), the liquid with higher temperature will first drop to the cooling environment temperature. If the temperature is lower than the freezing point of the liquid, the liquid with higher temperature will drop to the cooling environment temperature Freeze first.
Let’s take an example. If a cup of hot water and a cup of cold water are put into the refrigerator at the same time, which one will freeze first? In our daily thinking, cold water should freeze first. Is that absolute? Scientists use a lot of experiments to tell us that the results are not absolute. It is possible that hot water will freeze faster than cold water.
Although mpeba effect has been confirmed by scientists through experiments, it is difficult for many people to accept. Scientists have made many explanations for this abnormal phenomenon, but these explanations are difficult to convince people. At present, there is no definite answer. Of course, mpeba effect is only a part of the phenomenon. In most cases, cold water freezes before hot water.
Through the above five scientific theories, we can see that human cognition of the world is still very little. Although we have entered the era of science and mastered a lot of scientific theories, we are still very low-level in our understanding of science. Many scientific phenomena still make us confused and subversive. Only by making continuous efforts to develop science can we get more scientific theories and have more knowledge of material and the world.