We often use time to describe the passing of time, and time passes quickly. I believe that many friends have this feeling: When I was young, I felt that time flies very slowly, and I always hope that I can grow up quickly and become an adult.
But with the passage of time, as we grow up, we will feel that time has become faster and faster. Unknowingly, one day has passed, a year has passed, and a lifetime has passed. When we recall our childhood, we also feel that time at that time was indeed very slow, but why did time become faster and faster after adulthood?
Some people may say that this is an illusion. The flow of time in childhood is the same as the current time, and there is no difference in speed. The reason why we feel that the time now is getting faster and faster is mainly because we are doing our lives every day. Because of the pressure and busyness, I feel that time has become very fast. So is this really the case?
Perhaps in the eyes of ordinary people, the flow of childhood time is the same as the current time flow, and there is no difference between who is fast and who is slow. However, in the eyes of scientists, this problem is not that simple. Some people think that it may be related to the accelerated expansion of the universe. So in the world of scientists, how is this explained? Regarding the doubts about this time, scientists have proposed two conjectures.
1. Time changes brought about by the expansion of the universe
I believe that many friends know the Big Bang theory, which is our explanation of the origin of the universe, and it has been universally recognized. According to the Big Bang theory, our universe was born 13.8 billion years ago. At that time, a hot singularity had a big bang. Since then, everything in the universe and various laws have emerged.
After the universe was born, did it stop moving? Of course not. As early as 1928, astronomer Edwin Hubble discovered that extragalactic galaxies have redshifts and deduced Hubble’s law. Only then did people have a better understanding of the expansion of the universe.
By the end of the last century, Hubble observations gave us a better understanding of the depths of the universe and observed that distant galaxies are constantly moving away from us, thus confirming that the universe is accelerating. The expansion of the universe keeps the distance between galaxies moving away, and the farther away the galaxy is, the faster it moves away.
So what is the relationship between speed and time? Einstein’s special theory of relativity tells us that speed is inversely proportional to time. The faster the speed, the slower the time. That is, the faster the movement of the object, the slower the time acting on the object. If a person takes a light-speed spacecraft and leaves the earth for one minute, then after returning to the earth, the earth may have passed hundreds, thousands of years or even Tens of thousands of years.
So do people on the spacecraft have the same perception of this time as people on Earth? Some people may say that they are different, but in fact they are all the same, and the time has not changed. For the people in the lightspeed spacecraft, it will not feel that time has passed for a long time, nor will it feel that time has slowed down.
For people on earth, they also don’t feel the passage of time for a long time and the speed of time becomes slower, so the time of the two is the same. A friend gave a simple example: the movie was played at normal speed and took 90 minutes. At this time, the viewer wanted to see more details, so the movie was played at a high speed of 10% of the original speed. Next, the movie took 900 minutes to finish.
The movie’s playing time has changed from 90 minutes to 900 minutes. Has the movie’s time changed? In fact, it hasn’t changed. The content of the movie remains the same without any change. The same is true for the expansion of the universe. The farther away the galaxy is, the faster it moves away. Does the time of the distant galaxy slow down? Of course not, it becomes just the volume of space.
Therefore, the speed and slowness of time are only a kind of our feeling, and have nothing to do with other physical phenomena and theories.
2. The speed of time may be related to the age of the person
The first argument is that we explain the changes in time from physical factors such as the expansion of the universe, and the final conclusion is that the speed of time is just a feeling for us, and has nothing to do with other things.
But not everyone agrees with this answer. As early as 1890, a psychologist conducted an experiment in which he asked young people and old people to make a metaphor for time. And most of the young people gave a description similar to “the years are quiet and good.” However, the answers given by the elderly are different from those given by the young, and most of them are described as time flies.
Young people think that the time is just right and it hasn’t changed fast, but the old people think that time passes too fast and will come to the end of life in a blink of an eye. And experiments like this were repeated many times over the next 100 years, and the results obtained were surprisingly similar, which means that no matter when this experiment is done, young people and old people will get highly similar answers.
This shows that the speed of time in the eyes of young people is very different from the speed of time in the eyes of old people. Inspired by this experiment, the French philosopher Paul Janet put forward a special theory in 1897-the flow of time is related to the person’s age.
This theory holds that when you are one year old, one year is 100%, and when you are 50, one year only accounts for 2% of all life. The older you are, the proportion of one year will be The smaller. After such a theory was put forward, it was not recognized by many scientists. The reason was that the theory could not be established by a scientific model to prove it, and precise experimental results could not be obtained.
Although this theory has not been supported by many scientists, with the continuous advancement of human science and technology, more and more people are surprised to find that the things described by this theory may be true, and most people will be able to There is the above feeling, that is, the older you are, the faster time will pass. I believe my friends will not object to this.
So whether this relationship between time speed and age has a certain scientific basis, there is no answer yet. This is more like a philosophical theory of thought. Realistic experiments are difficult to give answers. Of course, the older people feel that time passes faster, it may also be a psychological effect. Of course, the truth is that scientists need to be able to get accurate answers in the future.