Introduction: Gravity is the geometric effect of the curvature of space-time, what does its underlying logic mean? Have you thought about it?
There are a lot of things I want to say, and I don't know how to say them for a while. When you don't know how to open a thing, it means that you don't know it in your heart, or it's not reliable. Everyone is a first-time person, stumbling, like crossing a river by feeling a rock. The same is true of human beings.
The more you know, the more you feel lost, and I'm sure that's what the great scientists must have been inside. My purpose and original intention of writing popular science seems to have changed slowly, not to tell people that you have to believe that time exists, you have to believe in the four-dimensional space-time theory... Purpose and original intent seem to turn into self-revolution, self-worship and self-consolation.
Who is awake on earth? No one seems to be. I share many people who believe that relativity is correct, that Einstein is right. Special relativity has changed our previous view of space-time, and general relativity has explained gravity. But the theory of relativity seems to bring as many surprises as it does. Have you really thought about the fact that the cause of gravity is the curvature of space-time? Are you for or against? Newton's theory of universal gravitation turned out to be the case for objects at low speeds? Now the theory of gravity can not be incorporated into quantum mechanics? A "gravity" has two sets of theories, divided into "high speed" and "low speed"; the entire physical system is divided into "classical macroscopic" and "microscopic quanta", and then look at knowledge such as inertia, electromagnetic force and so on... It's getting more and more interesting.
Why is it getting more and more interesting, you come to listen, I will say. General relativity says that gravity is the product of the curvature of space-time, which is the nature of gravity. That's right, folks, believe in Einstein's brain, who came to this conclusion after rigorous reasoning and imagination. Just because you don't understand what is space-time, what is the curvature of space-time, etc., you can't say that this thing is too mysterious. Don't forget how many times this theory has been tested by experiments, in the face of ironclad facts, you do not understand, you can only consider your own problems and abilities first. But this theory does have contradictions, and I wonder how Einstein himself thought about it? We all know that Einstein spent the second half of his life working on a unified field theory, but without success. In fact, Einstein's original intention was to unify the electromagnetic force and gravity, which is what he understood as a "unified field". Because Einstein died in 1955, and the powerful discovery was made in 1973, proposed by Gross and Hideki Yukawa and others. The discovery of weak forces was probably made in 1933, proposed by Enrico Fermi. So to be precise, Einstein knew that there are three fundamental forces in the universe: gravity, electromagnetism, and weak forces. Therefore, the historical conditions for him to be a unified field theory in the true sense are not available.
Having stated this fact, I would like to point out that gravity cannot be incorporated into the system of quantum mechanics, and the problem lies in general relativity, that is, Einstein regarded gravity as a geometric effect of the curvature of space-time in general relativity. What is the underlying logic of this? It means that gravity is not force! Or rather, it's a virtual force. So what is a geometric effect? I suggest that you simply replace the word "geometry" with "mathematics", i.e. gravity becomes a mathematical effect. That's the point where it's hard to accept. We say that the moon revolves around the earth because there is an invisible gravitational pull on the moon, so that it surrounds the earth, which is high school knowledge. After studying general relativity in college, you told me that this is an illusion, that gravity is a geometric effect, and that the curvature of space-time produces gravity. This bend is too urgent, many people can't react, no wonder we drive the car into the "ditch" and then climb up hard, so many years, it seems that we can't climb out.
The moon revolves around the earth, the earth revolves around the sun, that is the objective motion, the state of motion is changing all the time, and the force is the reason for maintaining the change in the state of motion of the object, and now it is said that gravity is not a real force, it is the geometric effect of the curvature of space-time. I really can't imagine it. But Einstein's argument is so fresh and well-founded that people have to believe it.
And teachers and scientists tell you that Newtonian gravity and Einstein gravity have their own strengths and are suitable for different situations, that is, they are all good, you see the situation. But the contradiction between Newton's gravity and Einstein's gravity has been shelved to this day, as if there is no way to explain it.
The question itself is the answer, and when a question cannot be explained, it means that it needs a better answer! So what is the answer to this? You think about it first.
Do you know what it means to admit that gravity is a geometric effect? In fact, it means that it cannot be incorporated into the quantum mechanical system, let alone unified field theory. Obviously, if gravity is the bending effect of space-time, gravity does not need the concept of gravitons, which is superfluous. The other three forces in the universe are all particles with transmission forces. The electromagnetic force is interacted by photon transport, the strong force is interacted by the gluon transport, and the weak force is transported by the W and Z bosons. What about gravity? If gravity were a space-time bending effect, there would be no gravitons.
Some online articles say that gravitons are considered from the level of quantum mechanics, and Einstein's theory of gravitation does not conflict with macroscopic interpretations, and gravitons are the transmitting forces of gravity in quantum mechanics. Do you think this explanation makes sense? I don't have the urge to evaluate.
If gravity is the geometric effect of the curvature of space-time, then even "gravitational quantization" is a superfluous word, so how can gravity be incorporated into gauge field theory without gravitational quantization. So that's why I say that there are as many surprises as the theory of relativity brings us, and there are as many questions as there are.
The contradiction in the understanding of gravity that comes with general relativity is precisely why it has been attacked by all sides. People always feel that there is something wrong with it, but it is not clear, so all kinds of modifications and accusations about relativity flock to it. The official [referring to the textbook] did not stand up in time, so the chaos has always existed. So is there really something wrong with the theory of relativity? The point is where is the problem?
Folks, don't think like that, you have to believe in that wave of extremely intelligent and hard-working scientists, who are no worse than us. And they held a skeptical attitude, constantly spending manpower and material resources to verify, the verification results are gratifying, Einstein and others are correct.
Is it true that we lack knowledge and imagination and have no way to understand the mystery? Yes, there really is such a situation, and it is really difficult to understand how he reasoned without understanding the constant speed of light, and without mastering the knowledge of flat space and Riemannian space. Don't talk about us, Einstein went from special relativity to general relativity for 10 years. Yes, you really should doubt yourself, after all, from three-dimensional space-time to four-dimensional space-time, there is a lot to understand. And four-dimensional space-time, and then to five-dimensional space-time, it is even more difficult. More than once, I tried to think about what the five-dimensional space-time looks like, and I'm sorry, but I feel that I have never gotten any specific information, and I can't think of what the five-dimensional is like.
So how to solve the chaos, let it continue to chaos? No, something has to be done.
Like many people, I have repeatedly looked at the conditions under which special relativity and general relativity are valid, and I can't find anything wrong, yes, special and general relativity are correct! In this way, I wondered how to explain the problem of the moment while acknowledging that it was correct. I tried to give an answer, which is that the theory is correct and wrong in the interpretation. What it means is that gravity cannot be explained as a geometric effect of the curvature of space-time, not as curvature of space-time. So how to explain it? Rather than being interpreted as a geometric effect of the curvature of space-time, it is interpreted as a property of space-time.
Looking back at the conditions for the establishment of special and general relativity, what concept does it point to? You should think about it. The answer is inertia. Looking back at Newtonian mechanics, what concept does it point to? The answer is still inertia! College students and doctoral students understand it at a glance. But junior high school and high school students may not understand it for a while, why do you say so?
Let me briefly say, what is the basis of Newton's three theorems? It is the law of inertia. And how did Newton's formula for gravity come about? Students who have deduced it in high school know that they cannot do without Newton's three theorems. And the conditions for the establishment of Einstein's special and general relativity, such as the principle of equivalence, the principle of general relativity, the principle of special relativity, which premise is not "inertia"? It is inseparable from "inertia". What is the source of Einstein's principle of equivalence? Is the inertial mass and gravitational mass strictly equal. The principle of general and special relativity is about the content between inertial and non-inertial systems. So you found that no, the concept of inertia is too important, and not understanding this is the root cause of our ignorance and confusion!
This is why I explicitly said in the popular science book "Change" that inertia is the cornerstone of modern physics! My heart-pounding idea of writing popular science also began from the point of "inertia", from this curiosity. Once the results started, they couldn't stop.
How do we explain inertia? Textbooks say that inertia is an inherent property of an object, it is a phenomenon of resistance, it exists in every object, the size is proportional to the mass of the object, and try to keep it in its current state, whether it is a stationary state or a uniform linear motion state.
That is, why an object has inertia, we do not know, we say that it is an inherent property of the object. But do objects have inertia for no reason? I was a little disbelieving, so I tried to answer that question. Obviously, because I realized that without answering this question clearly, you can't understand the physical "superstructure".
Friends who have read the previous chapters already know that the answer I give is: gravity makes objects inertia.
If you are more sensitive, now go back and think about Einstein's statement that gravity is caused by the curvature of space-time, combined with the two words inertia, you may be more enlightened. Because you think of the concept of "inertial force"! Everyone knows that inertial force is not a real force, but inertial force exists objectively! Inertial forces have a solid effect on ocean currents and atmospheric convection, which we call coriolis forces. What am I trying to illustrate? It's not that gravity and inertial forces are similar to each other, but it provides a different perspective on the role of things. In this way, gravity is no longer a geometric effect, and it is well-founded.
One might ask, why not understand gravity as a being like inertial force? In fact, it is very simple, understood as the existence of "inertial force", there are still many problems, gravitons, gravitational quantization, unified field theory... None of this is still possible. Some students will ask questions, can not be realized, must not achieve the unified field theory? Of course, this doesn't have to be achieved. But logically and philosophically, everything is connected, and we can naturally think of linking the fundamental forces under the premise of believing in this philosophical understanding, but now we cannot connect.
What to do? One of the two directions is to continue to "deepen reform" and start with the existing theory; the other direction is to simply abandon the existing theory, start another stove, and find another way to complete the theory of the great unification. Thus the application of string theory was born, and the basic force transmitted in string theory is no longer a variety of particles, but a vibrating "string". Similarly, while the theory brings surprises, it also brings problems, that is, high dimensional problems, and not generally high. It's so high that it can't be touched at all, like I said I can't even imagine what a five-dimensional space is, how can I imagine an 11-dimensional space? And string theory is not an ordinary person who "wants to play". It was a highly mathematical theory, and I couldn't understand it at an amateur level.
Back to inertia, this is a question you have to think about. Inertial forces are not forces, but why do inertial forces have a real effect on objects? Guys, this is a key question, circled, in my case, it is a compulsory question. Because you also have to ask, if gravity is not a force, it is a geometric effect, why can it have a real effect? There's nothing wrong with asking that.
Come, use your imagination and follow my train of thought. You now imagine a car with an iron ball hanging from a rope in the middle, the car accelerates forward, the iron ball in the car will swing backwards, if the car is accelerating at a uniform speed, then the iron ball will always swing backwards. This experience everyone should have, it is similar to the feeling of pushing back experienced by sitting in a car. The question is, why is the iron ball swinging backwards? The answer is definitely under pressure. However, there is no force object, and the students naturally say that it is because the iron ball has received an inertial force. But why is it subjected to inertial forces? As we continue to analyze, we will find that it is the movement of the car that makes the iron ball subject to an inertial force.
Inertial forces and real forces act in the same way, and the reason they are considered hypothetical forces is because we define forces as forces as interactions between objects. Inertial force can not find a force object, naturally it is not a true force. And our experience tells us that the faster the car accelerates, the stronger the feeling of pushing back, that is to say, the greater the inertia force. Why? Isn't inertia only related to quality? Yes, inertia is only related to quality, but inertia is not. According to Newton's second theorem F=ma, we can see that in the case of a certain mass, the greater the acceleration, the greater the force, which is why the push back feeling is stronger.
And I'm saying, can we think that inertial forces are generated by accelerated motion? Coincidentally, there is an effect in the theory of relativity called the mass increase effect. That is, special relativity holds that the inertial mass of an object increases with the increase of its speed of motion, and when the speed tends to the speed of light, the inertial mass tends to be infinite. Does this mean that exercise produces quality? This is difficult for the general public to understand. Exercise can produce mass, doesn't that mean that there is nothing out of nothing? The fact is that scientists have shown that the mass increase effect exists. So isn't there something out of nothing, isn't there still "movement"? You just have to answer why this effect is ok.
The mass of moving objects increases because the origin of gravity is space-time, and instant space makes objects gravitational. Space-time is essentially material space-time, energy space-time. For moving objects, additional energy is given to the object. That is, high-speed moving objects force space energy to "paste" on it, an effect similar to the "Higgs mechanism" developed in quantum mechanics. In fact, this is a state of bondage, which restricts the increase in the speed of movement of objects, which is why the speed of light cannot be surpassed. From Wheeler's classic general relativity statement: matter tells space-time how to bend, and space-time tells matter how to move. It is clear why gravity makes objects inertial, while space-time makes objects gravitational.
Inertia is universal, and gravity is universal. What is the reason for maintaining the motion of an object? It's inertia! Is it enlightening that you combine time and space to tell matter how to move? The two concepts of space-time and inertia have come so close for the first time. Thinking of space-time must think of the concept of a wide-area field, what is synonymous with space-time field? It's a gravitational field! So gravity is the root cause of the inertia of matter.
Some people will ask, why not just say that the space-time field produces inertia? In the first few chapters of "Change", I said that if this is done directly, there will be a hyperclide effect, and the speed of light cannot exceed the speed of light, otherwise it conflicts with the conditions under which general relativity is established. Do you know the Maher Principle? Mach's principle has a hyperclide effect, which is why mainstream science rejects him. But Einstein was inspired by Mach's principle and developed the theory of general relativity.
Gravity is also universal, so it is a wide-ranging effect, so it naturally comes to mind space-time. Space-time causes objects to gravitate. Therefore, the field equations of general relativity are also called cosmic field equations. Therefore, the fundamental difference between the gravitational theory of general relativity and Newton's theory of gravitational force is also clear, indeed due to motion. At low speeds, myopia is in the inertial frame, and Newtonian gravity applies; at high speed, in the non-inertial frame, general relativity must be used.
What is sub-energy must be something real. The gravitational field or space-time field must be something real, and it can theoretically be quantized. This is a positive signal for general relativity to be incorporated into quantum mechanics.
Now the strong force, the weak force, and the electromagnetic force are unified, but the gravitational force has not been unified. Einstein's commitment to unifying gravity and electromagnetism has not yet been completed. Also, if gravity can be unified with the electromagnetic force, it naturally means that the four forces can be unified.
Some readers have asked such a question: the Internet says that the magnetic field is the relativistic effect of the electric field, does not this mean that the electromagnetic field and the theory of relativity are related? That's too superficial. Magnetic field is the relativistic effect of electromagnetic fields, in fact, it is still said that magnetic fields can be obtained by the relativistic conversion of electric fields, and this transformation is close to special relativity, and has no direct relationship with general relativity. General relativity is the theory of gravity, so gravity and electromagnetic force have not yet been unified.
At this time, I also thought of a more sci-fi idea, probably like this, the physical world, virtual particles through the Higgs field to obtain mass, in the moment of obtaining mass, by the rules of the physical world bound and evolved [rules refer to the normative field theory system], thus forming the current flower world. We continue to assume that gravity is a geometric effect, so we can think of gravity as a bug in the real world because it is not real, it is mathematical. Then it is unexpectedly revealed that the world is ultimately mathematical, not real. So are all of you mathematical or real? Or is it that the bug of gravity is only a BUG in our dimension, and if we can recognize five-dimensional space-time, then understanding gravity is easy.
What do you think, what do you think? Don't forget, the world is mine and the world is yours.
December 31, 2021.
Independent scholar, writer, artist recluse of popular science. This article will be included in the book "Change" in the popular science book "Change".