How did Einstein discover that the speed of light does not change?

While the famous Michelson-Morey experiment did prove that the speed of light does not change, Einstein did not propose the principle of the invariance of the speed of light on the basis of the results of this experiment (at least not entirely, and it is likely that he was not aware of the Michelson-Morey experiment when the special theory of relativity was conceived in his mind). Isaacson (yes, the same person who wrote "Jobs") wrote a biography of Einstein, "Einstein: Life and the Universe", which clearly shows that the principle of invariance of the speed of light is likely to be a necessary hypothesis put forward by Einstein based on the electromagnetic theory that had been developed and matured at that time, that is, the principle of invariance of the speed of light was derived by Einstein through logical analysis based on the electromagnetic theory that had been verified at that time, rather than the experimental results directly adopted.

At that time, the theory of electromagnetism and the results of experiments puzzled Einstein a lot: "There was a more special kind of 'asymmetry' that began to bother him. When the magnet moves relative to the coil, an electric current is generated.

As a child, Albert Einstein already knew when he was tinkering with the generator at home that the current generated was the same whether the coil of motion of the magnet was stationary or the coil of motion of the magnet was stationary. He also studied Fipple's Introduction to Maxwell's Theory of Electricity, published in 1894, which included a section entitled 'Electrodynamics of Moving Conductors', which asked whether there was any difference between the motion of a magnet or the motion of a coil when induction occurred. "But according to Maxwell-Lorentz theory," Einstein recalled, 'it is difficult to theorize the phenomena of these two conditions.

For the former case, Faraday's law of induction says that the movement of a magnet in the ether creates an electric field. For the latter case, Lorenz's law of force says that the movement of a coil in a magnetic field produces an electric current. 'It's intolerable to me to think that there is an essential difference between the two situations,' Einstein said.

According to emission theory, the light emitted from the accelerating light source may recede on its own. "It is because of these reflections (and of course there is a lot of mathematics involved) that Einstein abandoned the emission theory and instead assumed that the speed of light is constant no matter how fast the light source moves. "As for the effect of the Michelson-Morey experiment on Einstein," according to Einstein, the effect was minimal.

In fact, he sometimes even (erroneously) recalls that he did not even know about the experiment before 1905. Of course, "Einstein's inconsistent statements about the effects of the Michelson-Morey experiment over the next 50 years remind us to be cautious when writing history from vague memories." From this, we can at least assume that Einstein's hypothesis of the invariant principle of the speed of light is not simply taken from experimental results, but also shines with the thoughtful and rigorous wisdom of a great scientist.

This scheme is particularly attractive if you think that light behaves like a beam of quanta. But this scheme is problematic. He seems to mean abandoning Maxwell's equations and wave theory.

If the speed of the light wave depends on the speed of the light source, then the light wave must carry this information in some way. But both experiments and Maxwell's equations show that this is not the case. Einstein tried to adapt Maxwell's equations to conform to emission theory, but the results were disingenuating.

This theory demanded that light waves with different velocities of propagation should be possible anywhere and in any particular direction,' he later recalled, 'and a reasonable electromagnetic theory that satisfies this condition seems impossible.' The more Einstein thought about the theory of launch, the more problems he encountered. As he explained to his friend Ehrenfest, it is difficult to calculate what happens when light emitted by a 'moving' light source is refracted or reflected by a stationary screen.

In fact, treating the speed of light c as a parameter, rather than as a constant, will not produce contradictory results within the framework of existing theoretical physics. But when the speed of light and the law of cause and effect are combined, the law of indefinite speed of light can have a huge impact! But now many experiments in quantum physics are quietly showing that the law of cause and effect does not seem to be so firmly entangled with the speed of light!

Whether dark energy is immortal or spiritual, the ultimate goal of a cultivator is to become an immortal and become a god, but when crossing the tribulation, the dark energy impact cannot be absorbed, resulting in the failure of the tribulation.

This is assuming that the light is the case of an airplane.

Because he is Albert Einstein.

Look in the mirror at the speed of light! If the speed of light travels at a speed of c in the ether, then flying at the speed of light and seeing your face again is twice as fast as c!

The change in the speed of light is related to gravity.

A person throws a small ball in front of him, and the velocity of the ball is 30m per second. If he sits on a car traveling at a constant speed of 100 meters per second and continues to throw the ball, then the speed of the ball is the superimposed speed of 130 meters per second.

The speed of light in a vacuum is 300,000 km/s. And then you sit in a car that is also traveling at a constant speed of 100 meters per second and emit a beam of light or a slag photon, and the speed of the light does not superimpose, that is, the speed of light does not increase because you sit in a car traveling at 100 meters per second.

This is the difference between a light without mass and an object with mass.

So, why does Qi Jing keep the speed of light the same?

Because the speed of light is 300,000 kilometers per second, even if you move fast, you can't run the speed of light, because you have mass after all, and you can't exceed the speed of light with mass.

Even if your motion is faster than the speed of light, it is only because you exceed the speed of light, that is, the light source exceeds the speed of light. But the light you emit will still maintain a speed of 300,000 km/s, and you will be left behind.

In this way, an invariant frame of reference is found, i.e., the speed of light is constant. Otherwise, there is simply no immutable frame of reference.

Why is it difficult for many people to understand that the speed of light does not change? Because when most people first hear that the speed of light is constant, they always subconsciously follow their own ideas and experiences of time and space to get their own answers. But in fact, when we say that the speed of light is constant, it often contains the meaning of three different levels, and when the speed of light at these three different levels is understood, all doubts can be easily solved.

<> speed of light is constant at three levels The speed of propagation of light in the same medium remains the same The speed of propagation of light in different media is different, but this is not to say that the propagation of light requires them as a medium, just to express that through light between them, the propagation of light does not require any medium), such as traveling in a vacuum, the fastest speed in air, water, glass, and slower, but the propagation speed of light in the same medium is constant, which is determined by the law of electromagnetism.

We now know that light is an electromagnetic wave, so light must also follow Maxwell's equations, from which it is easy to derive the speed of light (electromagnetic wave velocity). is the permittivity, is the permeability, they are fixed in the same medium, from here it is also easy to see that the speed of light is a constant in the same medium, it is only related to the permittivity and permeability. The speed of light does not change with the motion of the light source.

It's easy to understand that the speed of light doesn't change with the movement of a light source, but it's not just electromagnetic waves of light, but also our ordinary water waves. An axiom is something that cannot be proven to be true or not, and you have to accept it if you want to play. There are many theoretical systems in mathematics, you can come up with some axioms by yourself, and then derive some useful theorems based on these axioms, but you have to make sure that the system you build is self-consistent, to say that the simple point is to be categorical, don't be deduced by one theorem your system makes it say that the triangle is 180 degrees, and the other theorem says that the angles of the triangle add up to 240 degrees, so that your theory is directly finished.

Why is the speed of light constant in a vacuum?

Why is the speed of light constant in a vacuum, because Einstein's mass-energy equation: e=mc 2 revealed the law that the overall energy of the universe is equivalent to the overall mass of the universe, and found that the overall mathematical formula is also the original creator of the overall cosmology law, Wang Minsheng, revealed that the overall energy of the universe is equivalent to the space-time of the universe, z=e=mc 2=syw=stk 3, z=universe as a whole, e=joules, s=thinking subject, y=known number, y=unknown, t=time=seconds, k 3= cubic kilometers, Therefore, the speed of light is the critical point of the transformation of energy and mass, so the speed of light is constant in the vacuum of the universe.

There are positive and negative virtual particles in the vacuum quantum fluctuations - popular science, reaching the critical point to produce a large ** to produce matter to evolve all things, time is a change in space" - Wang Minsheng, Maybe the overall mathematics and the overall mathematical formula: z=syw, is a miracle that happened in China in the Internet era, and the overall mathematical formula is also the law of global cosmology, according to the overall mathematical prediction: it is the fifth force that can unify the four physical forces - the dynamic equilibrium force of the whole universe!

In the overall mathematical formula, Z=SYW, Z is the universe as a whole, S is the thinking subject, Y is the known number, and W is the unknown number.

The speed of light does not change because of the speed at which light travels in an electromagnetic medium. Photons are polarized medium-transmitting states of electrons. It is not a photon space leap state, the photon does not superimpose with the motion, and there is no Lorentz transform. See the theory of light and physics in the library to learn about new theories.

Even if the light is a wave and a field, it has the nature of a wave and the velocity of the field, and the speed of the field does not change, so the speed of light is the speed of the field in a vacuum. But the fluctuation of light in the medium is more obvious, and it is not the field speed anymore! Therefore, the prism can separate the light from the color!

The principle that the speed of light does not change. That's the speed of light in a vacuum, and vacuums are all relative, approximate. There is absolutely no vacuum, and all vacuums are approximate. Therefore, there is no such thing as the speed of light not changing, it is just an imaginary idea.

This guy feels strange when he sees that the light has not moved, how the speed of light has changed, and he has become Einstein. He couldn't see it clearly.

It means that a beam of light has the same magnitude in different inertial frames, and in layman's terms, the speed of light is a constant constant under any circumstances.

The meaning of this statement is that the speed of light in a vacuum is the same for any observer, without any change.

The speed of light is very fast, generally 300,000 kilometers per second, and the speed of light does not change in any way.

The constant speed of light is due to the fact that people have different understandings of the speed of light.

It's just a theory of relativity, what is there to say, is it very profound? Uninteresting....

The speed of light is the maximum speed currently known to man, with a defined value of c=299792500 100m s

The kinetic energy of the speed of light is infinite, and it is impossible to reach the speed of light according to current human cognition.

The problem of the physics of the speed of light and the speed of light has little practical significance in itself.

Einstein proposed this theory on the premise that relativistic thinking understands it.

The theory of relativity is based on the principle that the speed of light does not change, and once an object reaches the speed of light, it will never change, which can be described as the overlord law of physics.

In the eyes of the observer, the speed of light is always the speed of light.

When the observer is stationary, the light-speeder moves away at the speed of light.

When the observer increases his speed to chase the light-speeder, the light-speeder remains far away at the speed of light.

So, the limits of time to the speed of light are gone.

In the eyes of the observer, the Lightspeed Person's time has come to a standstill.

As an object gets closer to the speed of light, the time passage of the object seen by the observer slows down.

But speed is relative, and isn't the observer in the eyes of the speed of light also the speed of light? The observer's time also stands still.

At this point, time stands still of little significance.

Personally, in my opinion, the term "time standstill" is basically Einstein, joking with the fastest cosmic speed.

Therefore, most imaginary time machines and the like are driven by objects moving in a circle.

Only in this way can the observer in the eyes of the light-speeder seem to be truly still.

Because the speed of light is the fastest speed in the universe, it means that the problem reaches the fastest speed. It's not that time stops, it's that it slows down. The time it takes for an object to get from point A to point B is calculated like this:

The distance divided by the speed is equal to the time. That is, the higher the speed, the smaller the time. Because it is impossible for the speed of an object to exceed the speed of light, when the object reaches the speed of light, the four-dimensional space in which we exist will be distorted, and the object that exceeds the speed of light will jump in four-dimensional space with the object that does not exceed the speed of light!

Not in the same four-dimensional space. Because it is the speed that exceeds the limit according to the formula the distance divided by the speed equals the time, now the distance divided by the speed + (overspeeding) equals the time, so the time slows down. To take an easy-to-understand example, when an object is at rest, the velocity is 0, but the velocity is never equal to zero, it can only approach 0 infinitely, why?

You look at the formula above: distance divided by speed equals time, if speed is equal to 0, then the formula jumps, and the computer can't figure it out! Try it if you don't believe it!

What happens when it is less than zero, the distance is 3 meters, the speed is -1, then the time is equal to -3. Turn back the clock!