Difference Between General Relativity and Special Relativity

The study of physics has many things possible; in bigger areas like scientific experiments, technology, and in our day-to-day life. It helps us to understand many things, appliances and relations between objects, etc., with or without one’s knowledge. It helps us solve problems in daily life.

Many great scholars, physicians helped us understand physics and its laws with the help of their findings and theories. There are many such theories in the study of physics; Big bang theory, chaos theory, dynamo theory, quantum field theory, relativity theory, etc. are a few examples of theories that have solved such big mysteries and gave us knowledge about things happening around us.

General Relativity vs Special Relativity

The main difference between general relativity and special relativity is that general relativity is related to gravity and acceleration, whereas special relativity is related to speed and time. General relativity shows the relation between observer and acceleration, whereas special relativity shows us the relation between observer and constant speed when in motion.

General relativity theory is a theory that was published by Albert Einstein. It is known as the geometric theory of gravity. He predicts that the space-time around the planet earth is wrapped and twisted because of the planet’s rotation. Einstein started studying this concept in 1905, and it was completed and published in 1915.

Special relativity is a theory that shows the relation between space and time. It states that they are not different notions. It explains how that relation is linked for objects moving at a constant speed (in a straight line). According to Albert Einstein, this is based on two postulates – speed of light in vacuum and law of physics (same in all inertial frames). It is said to be published in 1905.

Comparison Table Between General Relativity and Special Relativity

What is General Relativity?

It is a theory proposed and published by Albert Einstein related to gravity. He says that the space-time around the planet earth is not only twisted but also wrapped because of the planet’s rotation. So that is the reason why there is a gravitational effect between the masses. He published this theory in 1915; it took him ten years to study.

When Einstein felt that the theory of special relativity was not sufficient in describing the whole universe, he, with the help of special theory, drew the general theory out of it. This theory describes gravity as the geometric property of space and time, as it also helped to refine Newton’s law of universal gravitation. It emphasizes the subject/ objects that experience acceleration.

It explains that space and time are the same but with different characteristics. The gravitation of force in and around the area of the object/observer depends on how curved the space-time is. The energy-momentum of the object’s matter causes the curve. The relation between matter and space-time is such that it tells each other how to behave.

The equation on the left consists of the given amount of mass and energy that distorts space-time and explanation about the way the energy, momentum, mass, etc., are distributed in-universe on the right-hand side of the equation. General relativity is said to be a more advanced theory. It is highly important as it is used and helps to predict or describe a few things like a black hole, time travel, and used in astronomy, nuclear physics, etc.

What is Special Relativity?

It is a scientific theory that was published by Albert Einstein in 1905; he published this in a paper titled ‘On the electrodynamics of moving bodies. Einstein developed this theory because of the failure of Newton’s mechanics and electromagnetism equations of Maxwell and Michelson Morley’s null result of his experiment. His theory corrects the mechanics of situations that involve all motions (especially the ones that have a speed close to that of light).

Isaac Newton has proposed studied the universe and proposed three laws of the universe before Einstein. But few things were missing, and the theory was not fully complete.  

Laws of physics remain the same in all inertial frames of reference. The speed of light in a vacuum is the same for everything, no matter what or how the motion of the source/ object is. Special relativity explains and shows as observers who show movement in constant velocity. It states that space and time are the same. In all inertial frames, the law of physics will be the same. It applies the phenomena in the absence of gravity.  

In simple words, the mass of the object becomes infinite when the object approaches the speed of light. Then it will not be able to go any faster than the light’s speed. It states that the mass changes as the object move; it is a function of its velocity, and the length of the object contracts in the direction of motion.

Main Differences Between General Relativity and Special Relativity

1. General relativity shows the relation of the observer and the acceleration, whereas special relativity shows the relation of the observer and the speed and time.
2. General relativity considers and includes gravity, whereas special relativity does not include gravity, as no forces are acting on it.
3. General relativity considers that the laws of physics are the same for all the inertial and non-inertial systems, whereas special relativity states that the laws of physics are the same for only the inertial systems.
4. General relativity was published in 1915, whereas special relativity was published in 1905.
5. General relativity talks about the curvature in space-time, whereas special relativity does not talk about any curves.
6. General relativity is more complex and covers a greater part of the universe, whereas special relativity is a little simpler and covers a lesser part of the universe.

Conclusion

Einstein has contributed a lot to the world of physics. His theories and findings have helped us understand and crack a lot of mysteries. If Einstein and other physicians wouldn’t have given their entire lives for this and had not done intensive researches, then the lives would be difficult. We would not have understood so many things, both basic and complicated.

Few theories work, and few don’t, but the inventions, theories, findings did not stop. Relativity theory was the basis of these two theories and has gained a lot of fame. General relativity is the subset and larger picture of the special theory.

References

1. https://books.google.co.in/books?hl=en&lr=&id=9S-hzg6-moYC&oi=fnd&pg=PR5&dq=general+relativity&ots=FJLRBJiEU9&sig=W52eaOvseveUPZ5Yy8_DIsLWYPQ
2. https://www.osti.gov/biblio/4351384