# TIME DILATION

One of the major consequences of the Special Theory of Relativity (STR) or the theory of relativity is the idea that time is relative and that time travels slowly under certain conditions.
It is an idea that is difficult for many to understand, understand and accept. But, as it is often mentioned in Hollywood movies, the concept is familiar.
It is a fact that time dilation or time travels slowly in certain situations. Not because it comes in Hollywood movies, but because many of us use this phenomenon in our daily lives, without even knowing it.

Google Maps or GPS navigation system is a mobile app that we have been relying on recently as we travel to a new place. In order for the system to work correctly, a correction proportional to the amount of time dilution required by the Special Theory of Relativity must be added to the clocks on the GPS satellites and GPS receivers. If it is not added, more than 10 km of error will occur every day in our locations where it shows up.

Moreover, time dilation has been proven many times over by scientists
Now let us see how or why time dilation occurs.
According to the Special Theory of Relativity, the speed of light is the same for all observers, regardless of the speed of the observer.
In normal life, when we travel in a bus at a speed of 50 kilometers per hour, when a car overtakes the bus at a speed of 60 kilometers per hour, it seems that the car is moving at a speed of 10 kilometers per hour. That is, you feel that the car is moving very slowly past you.

Even if the car is moving at a speed of 60 kilometers per hour, you will feel the speed of the car only 10 kilometers per hour as you have a speed of 50 kilometers.
This is normal relativity. Also called the Relativity of the Scientist Galileo.
Albert Einstein’s Special Theory of Relativity (STR) states that this logic does not apply to light. Not only does STR say that, but it is also found from many experiments with multiple repetitions. The Michaelson & Morley experiment is one of the most famous experiments in history.

The speed of light is 3,00,000 km / s
If you are traveling in an imaginary bus traveling at a speed of 2,50,000 km / s, if the light passes you and you still look, you will see that the light is overtaking you at a speed of 3,00,000 km per second.
Even if you have a speed of 2,50,000 km / s, you do not think that the speed of light is 50,000 km / s. Instead, you still think that the speed of light is 3,00,000 km / s.
Even if your bus is now at a speed of 2,99,000 km / s, the light will pass you at a speed of 3,00,000 km / s.
Doesn’t this sound weird.
Speed ​​= distance / time.
If the speed of light is to be the same for all observers, there is only one way, and for all those observers, distance and time will look different.
When time looks different to different observers, we call it time dilution. A person who travels faster than someone who is stationary seems to have a slower time.
When distances look different to different observers, we call it length contraction.
called (length contraction)
The above is called Velocity Time Dilation.
Then there is gravitational time dilation, which is related to the strange behavior of light in gravitational fields.