A galaxy 32 billion light-years away from the earth can travel 2.3 times the speed of light. Is it contrary to the theory of relativity?

This paper takes part in the series essay competition of “great science” of Recordunkown.

I believe many of you know Einstein and Einstein’s theory of relativity. It can be said that Einstein is the greatest scientist in the history of science for more than 300 years. His greatness is to put forward the theory of relativity, which guides human beings to explore the universe and its innumerable mysteries.

The understanding and application of the theory of relativity may only be superficial now. Even in a few hundred or thousands of years, the theory of relativity may still guide the scientific cause of human beings. The theory of relativity is a very great theory. This theoretical system is very huge. One of the important branches is that many people know that the speed limit of objects under the theory of relativity is the speed of light.


I believe everyone knows that Einstein set a limit on the speed of the object, which is the speed of light. According to Einstein’s theory of relativity, the speed of any object with a still mass can only be infinitely close to the speed of light. Only things with zero static mass can move at the speed of light, such as photons.

After reading Einstein’s theory of relativity, my friends are very worried about the future of mankind, because when we go out of the earth and see a broader universe. We all know how vast the universe is, and the distance between galaxies in the universe is based on light years. The diameter of the Milky way is 100000 light years, and the nearest galaxy is tens of thousands of light years away. In the vast universe, which often takes light years as the unit, the speed of light is nothing at all. It can be said that in front of the universe, the speed of light is only the speed of tortoise.

Even if our spaceship flies at the speed of light, we can’t travel all over the galaxy, we can’t get out of the galaxy, let alone explore the whole universe. If we do not have the ability to travel all over the universe, nature will not be able to uncover the innumerable mysteries of the universe. In the end, the universe can only be seen from a distance but not from a close view. If so, is it meaningful for human beings to rapidly develop space technology and explore the universe?

Is the speed of light really impossible to break through? When mankind stepped out of the earth, we began to explore the universe. The important tool for us to explore and observe the universe is the astronomical telescope. Through the astronomical telescope, scientists have been able to observe 2 trillion galaxies, of which the nearest extragalactic galaxy is only tens of thousands of light-years away, and the farthest extragalactic galaxy is tens of billions of light-years away.


By observing these galaxies in the universe, scientists found a fact that most of their spectra show red shift, and the farther away they are, the greater the red shift is. This means that extragalactic galaxies are moving away, and the farther away they are, the faster they are moving away. This is also the theory of big expansion of the universe. According to the cognition of modern science, the universe originated from the singularity big bang 13.8 billion years ago. After the big bang, the universe began to expand rapidly, which seems to be far faster than the speed of light.

If the average speed of expansion of the universe is the speed of light, then the diameter of the universe should not exceed 13.8 billion light years. In fact, the observable universe has reached 93 billion light years. From this value, we can see that the universe expands faster than the speed of light, and the speed of galaxies away from us increases with the distance.

In the 1920s, Hubble made a detailed study of the spectra of galaxies. The results show that the galaxies in the universe are not half blue shifted and half red shifted, but almost all of them are red shifted. Only a few galaxies near the Milky way are blue shifted, which indicates that the star systems are basically far away from the Milky way.


According to the Doppler effect, the wavelength of light will become longer when the light source is gradually away, which will lead to a red shift. However, the redshift of galaxies is not caused by the local motion of special relativity, because there is a more important law, which makes galaxies retrograde at superluminal speed.

We can think of the universe as an expanding balloon. The points on the balloon are equivalent to the galaxies in the universe. Therefore, when the balloon expands, the points on the balloon will be pushed away from each other. No matter from which point, the other points are retreating, and the farther away the point is, the faster the retreating speed is.

The retrogradation of galaxies in the universe is similar to the retrogradation of the upper points when balloons expand. As long as the space between galaxies expands enough in unit time, it will lead to the retrogradation of galaxies at superluminal speed.

And the scientists also calculated the speed at which galaxies move away from each other as distance increases, based on the Hubble constant. According to calculations, when the distance between two galaxies reaches 14 billion light-years, space expansion will make them separate from each other at the speed of light. If the distance exceeds 14 billion light-years, the galaxy will regress faster than the speed of light.


Seeing this, many people may have such a question: is it not against the theory of relativity that galaxies 14 billion light-years away are moving faster than the speed of light? The farthest Galaxy we can see now is gn-z11, which is 32 billion light-years away from the earth. At present, its retrogradation speed is 2.3 times the speed of light.

Does this superluminal regression velocity contradict the theory of relativity? Some people may think that since the expansion speed of the universe can exceed the speed of light, the theory of speed limit of light put forward by the theory of relativity is wrong. Is this really the case? In fact, this is not the case at all. The reason why many people have such misunderstanding is that they do not fully understand the limit of light speed in relativity.

In fact, when relativity talks about speed, it refers to the speed of an object relative to a local stationary space, that is to say, it is applicable to a stationary flat space without curvature. For example, on the earth or in a limited space, the curvature is basically flat, so the speed limit of an object at this time is the speed of light.


But the real situation of the universe is not a static flat space, but the curvature is constantly changing. This is also the category discussed in general relativity. If two objects are in different space coordinates, then when we talk about speed, we need to consider the curvature change of space-time itself. Under the influence of curvature, there is no limit on the speed of light.

The real universe is full of species and energy, and under the action of gravity, matter and energy, the space-time structure will change with time, resulting in the change of space position. Especially close to some super massive objects, the curvature of space structure changes more seriously, which is what we call space distortion.

If we can see the distortion of space, you will find that the whole universe is equivalent to a network structure. If there are celestial bodies in the space, the network will deform. The more massive the celestial bodies are, the more severe the deformation of the network will be. It is precisely because the universe is not a flat structure, but a constantly distorted space, so even if the object in the universe is still, it will show the gravitational effect.

So satellites can orbit around the earth at a high speed. If our spaceship drifts in the space, it will drift in the direction of massive objects. Space is like a conveyor belt. Even if the objects on the conveyor belt are stationary, the moving conveyor belt will move with the objects on it.


The fact that galaxies are far away from each other in the universe does not mean that they are moving at superluminal speed, but that the expansion of space structure drives them to move at superluminal speed. This phenomenon is totally different from the velocity probability in the theory of relativity, so the expansion speed of the universe and the regression speed of galaxies exceed the speed of light, which does not violate the theory of relativism.

It is the observation and discovery of the expansion and distortion of the universe by scientists that has rekindled hope for the future exploration of the universe. Although our spaceship can’t exceed the speed of light in a flat space, we can use the distortion of space to make the spaceship fly faster than the speed of light. This kind of flight mode, we can call it space jump or wormhole shuttle.

No matter what kind of superluminal shuttle mode we want to achieve, it is not so easy. We need to twist the space around the spacecraft at any time. Only when the space is distorted more, can we get a higher speed of the cosmic conveyor belt, and can we go faster than the speed of light. To achieve this, we need to have enough knowledge of the universe, and also need a super powerful energy, which may only be achieved by the dark matter and dark energy that we have been exploring.


Guys, what do you think of this? Welcome to leave a message to discuss and express your opinions.

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