Question

is this thing is true...

Answer 1

Heya!!!

This is a very very very complex as well as complicated topic to understand.

Firstly, the most important thing u need to learn is: time is not constant quantity.
 Never think that time is same everywhere. Its not constant.  

Suppose that there are two twin sisters. One of them stays in this world, the other goes on a space journey during which she travels almost at the speed of light. When she returns from space, he will find that her twin sister is much older than he is. The reason for this is that the time passed much more slowly for the sister who went on the space trip. The same example can be thought of in relation to a father who went on a space trip in a rocket traveling at nearly 99 percent of the speed of time and his son who remained on this earth. According to Einstein, if the father was 27 years old and his son was three, 30 earth-years later when the father returned to earth, the son would be 33 and the father would be 30 years old.

Confused??  No wonder u get confused. To understand this very clearly, we must be Einstein for sure. But if we do  a lot of research u will surely find some satisfactory answers.

the relativity of time is not something that is relative to the speeding up or slowing down of the clock; it comes from the fact that every material system, to the particles at the subatomic level, works at different rates of speed. In an environment where time was slowed down, a person's heartbeat, rate of cell division and brain activity would happen more slowly. In this situation, a person would go about his daily business unaware that time had slowed down. 

So,  my friend, the notes u wrote is absolutely correct. But, it seems to be wrong until u do some research. I recommend to see some youtube videos regarding this topic which r the best.

                           Hope this helps u , if yes, pls mark me as brainliest::))))
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