What is relativity?
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Relativity is a theory proposed by Albert Einstein. This broke the traditional understanding of time as a constant entity and proved that time is different for different observers. Let us see how…
What is relativity?
Let us understand relativity. Time- we can’t see it, feel it or hear it but we experience it in our every walk of life. But is time same for everyone??? For understanding this let us go back in time in the period of Albert Einstein.
To understand relativity, let us take an example. Imagine you and I are travelling in a train moving with uniform speed. Relative to the outside environment, the train is in motion; But we both sitting inside the train observe each other as stationary objects. This is because we both and the train are moving at the same speed. Thus we may conclude that we are stationary relative to the train. Laws of physics would act the same on us inside the train as they will on the ground. Now let us consider you get of the train and observe the train moving. Now you are stationary and relative to you I am moving with the same speed as the train.
Does everything follow relativity?
The phenomenon explained earlier is a natural phenomenon of relative motion which we observe every day. Even everything in the universe observes this phenomenon the same way- except for light. Because the speed of light is always constant regardless the motion of the light source. Let us take another example to understand this. The speed of light is almost 108,00,00,000 km/hr. Imagine that I am travelling on a straight road in a car with a torch (a light source). For the sake of simplicity, let the speed of car be uniform. Now, the car can attain a speed of 200 km/hr at the highest. If the speed of car is maximum, the light of my torch will travel at a speed of 108,00,00,200 km/hr. Compared to the speed of light, this difference of 200 km/hr is very less. Thus the average speed of light will still remain 108,00,00,000 km/hr only. Thus the phenomenon of relative motion doesn't apply to light due to its immense speed.What is classical relativity?
This was the basis of relativity known as classical relativity. So concluding, the theory of relativity simply states that it is not enough to ask how fast I am moving, instead we should say how fast I am moving relative to something. This is the principle of relativity. If you only ask how fast I am moving, your speed will encompass of the speed of earth, solar system, galaxy, or even universe. Now that is another topic.What is special and general relativity?
Albert Einstein studied this phenomenon and proposed it in 1905. His theory encompasses two interrelated theories- special relativity and general relativity. Einstein studied general relativity from 1907 to 1915 and published it on a paper in 1915. Special relativity also came to existence in the 1920s.
Special relativity applies to elementary particles and its interactions whereas general relativity applies to cosmological gravitation including astronomy. Now let us see some consequences regarding these theories...
What are some consequences regarding general relativity?
Consequences regarding general relativity include:
- As gravity increases the time slows down. The best example for this consequence is the black hole. As you move towards it, the gravity immensely increases it seems that time dilation has took place.
- Light bends due to presence of a gravitational field. This consequence is related to Einstein's another theory of the fabric of cosmos.
What are some consequences regarding general relativity?
Consequences regarding special relativity include:- Events simultaneous for one observer, may not be simultaneous for another observer if the observers are in relative motion. If I am in a bus, I am stationary for myself. But for the people on the ground, I am in motion.
- As our speed increases, time slows down. This phenomenon is called as time dilation. Moving clocks are measured to tick more slowly than a stationary clock.
- Length Contraction: Objects are measured to be shortened in direction that they are moving with respect to the observer.
- Maximum Speed is Finite. Speed greater than light can not be obtained.
Posts before October 2021 have been marked as "Old Posts". Less likely, but they might have out dated or incorrect information, ugly looking bits of code, no labels, etc. Don't get me wrong, many of these posts are top-notch and interesting too.
I thought it would be better not to delete or revamp these posts, even if they suck. The bitter truth is that old works always suck, but I take that as a positive tool to convey that I am growing. Besides there's no better way to showcase my journey without these old, messy, poorly written posts!
I thought it would be better not to delete or revamp these posts, even if they suck. The bitter truth is that old works always suck, but I take that as a positive tool to convey that I am growing. Besides there's no better way to showcase my journey without these old, messy, poorly written posts!
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