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Time is what separates the past from the future, without time there is no future and past, but in our world, the same second can feel very long and can also feel very short, people always measure the duration of things in terms of time.
In 1915, Albert Einstein created the general theory of relativity, which is very interesting because it shows that time is not an absolute concept, and that different people can feel different speeds of time passing, and in different places, they may feel that time passes at different speeds.
Einstein believed that in the universe, gravity causes the expansion of time, that is, time can become long and may even stagnate, so in the universe, time is very flexible.
Different objects will feel the speed of time passing at different speeds, so is there any object that can feel the speed of time passing the fastest?
Is there any object that passes the most slowly?
1. The difference in the speed of time passing.
To understand the difference in the speed at which time passes, we first need to understand how time passes.
In 1905, Albert Einstein proposed the special theory of relativity, which showed that time and space can affect each other, and that time and space are not absolute.
Einstein also gave what is the speed of light in a vacuum, in the absence of other matter, and without other forces, the speed of light does not change, it is a constant, and its value is about 3*10^8 meters per second.
However, Einstein's discovery that the speed of light has nothing to do with the relative angle of view, in other words, no matter what state you look at, you will find that the speed of light is constant, which is a bit awesome.
Therefore, we can understand that light has a very powerful property, that is, with the movement of different objects, its speed does not change, which is the reason why we know that matter cannot exceed the speed of light, however, there is an interesting phenomenon, matter can reflect the beam back, and at the same time, the beam can also be absorbed by matter, that is, the interaction between light and matter is reversible.
When Einstein studied a series of properties of light, he found that not only light has this property, but time also has this property, unlike light, for our world, the speed of matter movement can be changed, after time is changed, it is difficult to return to the original state, people always see the past as unchangeable, and the future is full of infinite possibilities.
Therefore, time separates the past and the future, and if you want to make time faster or slower in some way, you need to change the speed of the movement of matter, Einstein found through various calculations and experiments that the slower the object, the faster time passes, and the faster the object, the slower the time passes.
This phenomenon is known as the difference in the speed of time lapse, and its mathematical expression is that the speed of time lapse = 1/root sign (1-v^2/c^2), where v is the speed of the object moving and c is the speed of light in a vacuum 3*10^8 meters per second.
It can be seen that when the speed of the object is 0, the speed of time lapse is equal to 1, and when the speed of the object is equal to the speed of light, the speed of time lapse is equal to infinity, that is, time is basically frozen.
An object with a time lapse velocity of 1 feels the same speed of time as it is felt by an immobile object, that is, there is no relationship between time and the state of motion of matter, and it still conforms to Newton's law of inertia.
However, objects with a speed of time passing at a speed other than 1 will feel the difference in the speed of time passing, with the slower the object feeling the shorter the time, and the faster the object feeling the longer the time.
In addition to the state of motion of objects, there is another factor that will also affect the speed of time passing, that is, gravity, gravity will also change the state of motion of matter, and will also affect the speed of time passing, similarly, the stronger the gravitational force, the slower the speed of time passing, which is in line with the intuition of ordinary people.
For example, the gravitational pull on the ground is relatively small, so the speed of time that people perceive on Earth will be faster, and the higher the gravitational pull of an object, the slower time people will feel in its vicinity.
However, in Einstein's general theory of relativity, gravity can also be seen as a pseudo-force, except that this pseudo-force is due to the curvature of space-time in four dimensions.
Therefore, when Einstein studied the relationship between gravity and time, he found that the speed of matter is not only limited by the speed of light, but also affected by gravity, which will also compress the degree of freedom of matter motion.
The existence of gravity is the essence of general relativity, and the nature of this gravitational force can be described not only by Einstein's field equations, but also by Einstein's four-dimensional theory of space-time.
In short, no matter how gravity affects the speed of time passing, it will slow down the time pass, so the faster an object moves in the universe, or the closer an object is to a large gravitational source, the slower the time passes.
Einstein's general theory of relativity also gave many surprising conclusions, such as when studying supermassive black holes, it was found that near the event horizon of the black hole, it is impossible to escape the black hole, that is, once you enter the event horizon of the black hole, you will be swallowed by the gravitational pull of the black hole.
However, black holes do not allow all matter in the universe to be swallowed, and time in the universe expands in a very complex way, a phenomenon known as time dilation.
The process can be described by Einstein's field equations, and this time dilation tends to occur near supermassive black holes, and does not cause the destruction of the universe, but its existence can also have a very large impact on the universe.
2. Time dilation in ancient mythology.
Although time dilation may sound like a fantasy phenomenon that can only be found in science fiction or ancient myths, it actually exists in Einstein's theory of general relativity.
However, in ancient mythology, there is also a phenomenon of time dilation.
In ancient times, people had not yet invented any tools or equipment to measure time, so people's perception of time was often different from the time we measured, for example, in ancient times, people said that a day in the sky, a year on earth, this time phenomenon is similar to Einstein's deduced phenomenon of time dilation.
Of course, the day in the sky that the ancients spoke of refers to the speed at which time passes in the sky, and this speed of passage is of course the time in the sky, and the year on earth refers to the time on the ground, and this speed of passage is of course the passage of time on the ground.
Correspondingly, there will be a difference between the time of human existence and the time of the sky, and this difference will be affected by the speed of matter in addition to people's subjective feelings, although the current speed of human matter cannot reach the speed of light, so the difference in the speed of time passage that people feel is very small.
However, if we calculate according to the ancient mythology of the heavens, heavens, and the earth in one year, then we can simply use some physical common sense to explain, such as the time dilation caused by high-speed flight, of course, this time dilation is not much to experience in today's human civilization.
However, in the past, human flight speed was very slow, and when airplanes became the standard equipment for human travel, people were able to travel more efficiently, and at the same time, they could carefully observe the surrounding environment, thus bringing more creative inspiration to people.
When human beings set foot on the moon again, the speed of time on the moon, that is, the time on the moon can feel faster than the time on the earth, because the mass of the moon is small, on the moon, because there is no environment on the moon, there is no air and other substances that will affect the speed of the movement of objects, so people on the moon will be faster than the earth, which is consistent with the results stated in Einstein's theory of relativity.
However, when people try to fly at higher speeds, the difference in the speed of time will be reflected, and this phenomenon will be very obvious when the speed of human flight is approaching the speed of light, which is exactly what ancient mythology describes as a day in the heavens and a year on earth.
On the other hand, the incredible difference brought about by Einstein's general theory of relativity is also reflected in the meeting of the Cowherd and the Weaver Girl in ancient myths.
3. The meeting of the Cowherd and the Weaver Girl.
The Cowherd and the Weaver Girl as a very famous story in ancient China, its plot and explanation are also very simple, in this story, the Cowherd and the Weaver Girl can be explained by time dilation, although this story may be just a mythological story and did not really happen, but people can understand the phenomenon of time dilation through this story.
According to ancient mythology, although the Cowherd and the Weaver Girl liked each other very much, they could not see each other due to time dilation and other reasons, and finally reflected in the world, and they could only meet on the Tanabata Festival in the world.
Most people just tell this story as a love story, but we can also interpret it from a scientific point of view.
When human civilization was very low, the speed of human beings was very slow, and when people went to the vicinity of the Yellow River Valley in the east, they found that the environment here was very conducive to agricultural production, so people began to settle here and use it as the center of human development.
At the same time, when people are working in the fields, they will also observe various regular phenomena in the sky, which are very curious and worthy of in-depth exploration.
But when people dig deeper, they find that the various phenomena that occur in the sky are very complex, and these phenomena occur very quickly, often calculated in days, that is, the speed of movement in the sky is much faster than that on the ground, so people define the difference between time in the sky and time on the earth as a day in the sky and a year on the earth.
The story of the ancient Cowherd and the Weaver Girl can be divided into two parts, one is the speed of time passage on the Cowherd's side, and the other is the time lapse speed on the Weaver Girl's side, this difference is also reflected in human society, the Cowherd refers to the peasants, at this time the material movement of the peasants is very slow, and the Weaver Girl refers to the handicraftsmen, due to the existence of the handicrafts, the human travel speed is very fast.
The distance was too far for the farmers to communicate with the craftsmen, hence the story.
On the other hand, this difference in time dilation can also be explained by the effect of the sun's gravitational pull on the speed of time passing, the cowherd refers to the farmer, the farmer farms often during the day, and one can see the effect of the sun's gravitational pull on time during the day.
The gravitational pull of the sun is very strong, so the speed of time passing is very slow in the vicinity of the sun, while the weaver girl refers to craftsmen who are able to make in the dark night, so the effect of the sun's gravitational pull on the speed of time cannot be observed in the dark night.
This case is also very consistent with Einstein's theory of relativity, and if the two phenomena can be combined, then people's understanding of the speed of time can also be expanded.
epilogue
Although the difference in the speed of time proposed by Albert Einstein reflects the relativity of time, they are also used by humans to measure the duration of various objects and natural phenomena.
If human beings can master faster speeds or greater gravitational pull in the future, then perhaps human beings will be able to truly feel the difference in the speed of time passing, which will also bring infinite possibilities for human beings to continue to explore the mysteries of the universe.