You all must know that I have just initiated our first series of Space talks under the name of All About Space. In this series, I will try my best to explain each and every concept of Space and some related topics which will be posted daily. If you want a particular topic to get explored then you may comment down or text me on our Facebook page or our any other social media account. So without wasting time, let us get to today’s topic.
-: THEORY OF RELATIVITY:-
All of you may have heard about this theory, which is given by the synonym of genius, the Albert Einstien. This is one of the historic theory which has aimed to change humanity.
This theory is one of the by-products of the thought experiment done by Albert Einstien. The people who are unaware of Thought experiment subscribe to our newsletter because I will be posting another blog over it some other day for sure.
Now, what is so special about this theory?
Einstien gave the theory of relativity and it comprises of two inter-related topics, special theory of relativity and general theory of relativity. He worked over them from 1907 to 1915. And those theories stated that (special theory of relativity) speed of light is a constant and does not change for any observer throughout the space and the laws of physics hold true for an observer in uniform motion in any part of space.
This theory shook our previous beliefs on space. It explained how time was related with space, Einstien represented the concept of Time Dilation, which is widely used in many science fiction movies. This theory also talks about the mass-energy equivalence and here comes the famous equation of Albert Einstien, E=MC2. This theory also represents an argument that when anybody moves in any particular direction then the length of the object begins to contracts in the direction of the motion. This theory entitled the velocity of light as the ‘Cosmic speed limit’.
Now, what other half says(General Theory of Relativity) ??
This explores a level up to time dilation, which is gravitational time dilation. The theory also explains how the light is affected by the gravitational fields. Lastly but not the least, it agrees with the Edwin Hubble, a scientist who explained that the Universe is expanding, this theory not only agrees with him but also put forward an argument that the farthest parts of the universe are moving away from us with the speed more than the speed of light.
Now some of the explanatory parts, what is TIME DILATION?
Time dilation is one of the main features of the Theory of Relativity, time dilation means the change in time. Time dilation is of two types:-
- Velocity Time Dilation:- Suppose a spaceship moves at a higher speed with a light clock, they are nothing but a glass where a ray of light goes up and gets reflected back to the place where it begins and again goes to get reflected. So, consider two observers, one at the earth and other on the spaceship. The observer on the Earth will notice the straight motion of light inside the glass( light clock), but when he will make an observation on the clock at the spaceship, he will conclude that the light clock on the spaceship is not going straight instead it is going diagonally forming a right-angled triangle. But for the observer on the spaceship, everything is normal. This effect is caused because light’s speed is constant and it is moving upwards and then downwards. So, what happens is that when it goes upward there is a relative movement of the spaceship, so instead of going straight up and down, it goes diagonally up and diagonally down. This means that the light will have to travel a longer distance than normal, so time for the spaceship with respect to the time for an observer on the Earth is a bit slow depending upon the velocity of the spaceship.
T(changed)=T(stationary observer)/(1- v2/c2)1\2
2. Gravitational Time Dilation:- In gravitational time dilation, the time near the gravitational field areas get stretched and hence the time for the observer near any high gravitational field moves less as compared to the time for an observer away from that gravitational field area.
T(changed)= T(stationary observer) * (1 – 2GM/rc2)1/2
For better understanding lets take an example of satellites. Satellites time is adjusted before launching since they are aware of time dilation, all thanks to Albert bro!. Now when the satellite is in the space away from the gravity of the Earth and moving with a high speed. Both of the time dilation works together. The speed time dilation comes into action as the speed of the satellite with respect to the observer on the Earth is more so, the time for satellite must but be slow but since it is away from the gravitational field of the Earth, so the inhabitants of the Earth experiences the slow time as compared to the satellite, here gravitational time dilation comes into play. It slows the time for satellite as compared to the time on the Earth, therefore we have set the clocks faster so that they can match the time of the Earth.
If you have any other queries then please feel free to use the comment box. I will try my best to solve your problems.