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What is the meaning of "speed of light"?
Why can't this speed be surpassed?
Bao Tong, a physicist who was invited to the physics conference in Moscow, happened to have this question in mind, so he submitted some of his views on the insurmountability of the speed of "light" at the conference.
Speed of light.
The concept of "speed of light" was first formally put forward by the British physicist Maxwell, and according to his theory, light is a kind of electromagnetic wave, and the basic physical formula related to electromagnetic waves is reflected in the basic formula created by Maxwell.
The speed of light c as a constant has become one of the foundations of Maxwell's formula, and the speed of light is not only a constant in the vacuum propagation speed of the electromagnetic field and the light field, but also a prediction of the special theory of relativity in the motion of a superluminal object.
In 1880, Maxwell's reaction to the light field was the same as that of the electric and magnetic fields.
His success in the laboratory proved that the light field is a combination of electric and magnetic fields, and that light can travel freely in a vacuum without a medium, so Maxwell believed that light is an electromagnetic wave.
Therefore, he has been thinking about the correlation between electromagnetic and magnetic fields in the study of electromagnetic and magnetic fields.
And it was in 1878.
The German physicist Hertz measured Maxwell's theory of electromagnetic fields, he used a metal ring device to amplify the observation phenomenon of electro-light, and used a large switch to control the current on and off, when the current flows into the circle, a magnetic field will be generated, thus producing electromagnetic induction, the main purpose of the experiment is to observe the effect of this magnetic field on the emitted light.
In this experiment, he observed that when the frequency of the magnetic field is the same as the observed emission frequency, the emitted light will gradually weaken and tend to burn out, and through this phenomenon, he believes that the electromagnetic field is a combination of the electric field and the magnetic field of light, so he believes that Maxwell's theory is correct.
It can be said that light is a kind of electromagnetic wave, and Maxwell was very excited when he heard this rumor, and he thought that after years of research, his electromagnetic field theory had finally been realized.
And immediately sent a telegram to Hertz in Germany to congratulate him, also rejoicing at this achievement.
Maxwell's formula for electromagnetic fields has made a profound contribution to the study of light.
Regarding the propagation of light, in fact, after Maxwell published the theory of the electromagnetic field, the physicist Carl Whitge College published the book "Principles of Electrodynamics Different from Theoretical Machines", which theoretically deduced Maxwell's electrodynamics.
In the book, he also mentioned Maxwell's theory of electromagnetic fields and the propagation of light in Hertz's experiments.
He believed that Maxwell's electric and magnetic fields had their own physical properties, and he believed that Maxwell's theory that the electric and magnetic fields were a combination of elastic group forces, so he could conclude that light is a transverse wave.
Moreover, electricity and magnetism oscillate perpendicular to each other, so he and Maxwell's views on light are consistent to a certain extent, and Maxwell and Whitday's electromagnetic theory laid the physical foundation for the study of light.
Subsequently, Einstein conducted an in-depth study of Maxwell's theory of electromagnetic fields.
The theory of "speed of light" was derived from the experimental data, and through a series of mathematical derivations and experiments, the conclusion of the theory of relativity was reached, the speed of light is equal to a value of 299792458m/s, and the experimental data tended to be true, so later generations of physicists took this phenomenon as the basis of their research.
The famous "Hubble's Law" and "Black Hole Theory" are based on Einstein's theory of relativity, and Einstein's theory of relativity also mentions the curvature of space-time and the nature of the speed of light, so in people's cognition, the speed of light is undoubtedly a very important physical concept, so why can't the speed of light be surpassed?
What about Bao Tong's "speed of light" theory?
The speed of light cannot be crossed.
In order to prove the theory that the speed of light cannot be crossed, Bao Tong combined the electromagnetic wave of light with the formula of electromagnetic field and electromagnetic field according to the electromagnetic wave and light, and came to the conclusion that the "speed of light" cannot be surpassed through simple mathematical derivation.
In mathematics, he mentions gauge tensors in Riemannian geometry.
The gauge tensor is a way to describe the relationship between space and time, and it is also a kind of curvature of space-time, which is a fourth-order square matrix.
An important feature of tensors is that they are not constrained by reference frames, and they are invariant between arbitrary frames of reference, so Bao Tong not only found their correlation in the theory of electromagnetic fields and light.
At the same time, he also proposed a new research direction from the perspective of mathematics to study the solution of Einstein's field equation of light, and he believed that by solving Einstein's field equation, the conclusion that the speed of light cannot be surpassed can be obtained.
However, Einstein's field equation is a complex tensor equation, which is a very difficult problem to solve.
Therefore, after Bao Tong raised this question, some scholars quickly answered it, but they could not find a suitable solution, and Einstein, as an academic champion at that time, did not solve it clearly, so Bao Tong regarded it as an important research direction.
From this direction, Einstein's theory of relativity was studied in depth.
And when the object is in motion, the propagation speed of electromagnetic waves from its perspective is not greater than the propagation speed of light, so the speed of light is a constant number.
Even if the object is moving, it does not change the speed of light propagation, so when moving faster than the speed of light, this problem does not exist at all.
Faster-than-light phenomena.
However, in 1992, American physicist Galenner formed a research team to study the phenomenon of faster-than-light, but physicists did discover the phenomenon of faster-than-light in related research, which was the first time it was discovered in experiments.
So there was a lot of discussion about this phenomenon, and in this experiment, physicist Gelena used a particle called a superfermion, which is a metal made of superconductors and copper that was placed at low temperatures.
At this temperature, its resistivity decreases rapidly, and a very strong magnetic field is formed inside the conductor under the action of electric current.
The electromagnetic force formed by this superconductor at low temperatures is already beyond ordinary matter, so it can be used as a faster-than-light item.
In Gelenner's experiment, he placed this superconductor under the bombardment of high-energy particles to form an open ring, and then by analyzing the attenuation of this effect, he finally calculated the time interval for the particles to pass through the ring through the data, and the result was less than the time interval of the bombardment, which was the first time that the phenomenon of superluminal speed was discovered in the experiment.
And in 2012, the Swedish Academy of Sciences discovered a similar experimental phenomenon, they bombarded graphene to form a similar channel, calculated by the time interval after the bombardment, and also obtained results less than the bombardment time, these experimental results have posed a new challenge to physicists' cognition.
In 2018, physicists in the United States were even more surprised to find that when you quantum-entangle two superconductors, and then let a superconductor and an ordinary conductor be quantum-entangled, when bombarding the superconductors entangled by ordinary conductors, physicists actually found that although the distance between these two superconductors is far or near, they will perceive at the same time. So this kind of induction is a false faster-than-light induction.
If the theory of relativity is only a prediction that the speed of light cannot be surpassed, then the explanation of the theory of relativity is far-fetched, but through these experiments, it can be clearly seen that the high speed of atomic energy cannot exceed the speed of light, so some properties brought by the speed of light will naturally be inherited.
epilogue
The question of the speed of light transcendence raised by Bao Tong at the conference has been greatly questioned, and some physicists have raised some questions, but with the experiments done by physicist Gelena in 1992, there are finally some answers, and these experiments are used to study in reverse, so the conclusions of these experiments are a reasonable explanation.