 # Theory of Relativity

##### Theory of Relativity

The theory of relativity discussed the way in which the observers who remain in a state of relative movement explain the physical phenomenon. The theory of relativity explains how area and time are connected for things that are moving at a constant speed in a straight line. Among its most popular aspects, focused objects moving at the speed of light.

Before Einstein, astronomers (for the most part) comprehended the universe in terms of 3 laws of motion presented by Isaac Newton in 1686. But there were breaches in the theory for years prior to Einstein’s arrival on the scene. In 1865, Scottish physicist James Clerk Maxwell demonstrated that light is a wave with both electrical and magnetic elements, and validated the speed of light (186,000 miles per second). Researchers supposed that the light had to be transferred through some medium, which they called the ether.

There are 2 parts of the theory of relativity:

##### 1.General Theory of Relativity

The general theory of relativity handles the issues including frames of references accelerated with respect to each other.

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##### 2.Special Theory of Relativity

The theory of unique relativity was developed by Albert Einstein in 1905, and it forms part of the basis of modern physics. After completing his work in unique relativity, Einstein invested years considering what would take place if one presented acceleration. This formed the basis of his general relativity, published in 1915. It has two postulates which can be specified listed below:

1) The laws of physics are the same in all inertial frames of reference.

2) The speed of light in free space has the exact same value in all inertial contexts in all instructions.

The “relative” means?

Prior To Albert Einstein, researchers thought that all movement took place against a reference point called the “ether”. Einstein declared that the ether did not exist. He said that all movement was “relative”. This meant that the measurement of the movement depended on the relative velocity and position of the observer.

##### Outcomes of the Theory of Relativity
###### Time dilation

According to the special theory of relativity, time is not an absolute quantity. it relies on the movement of the frame of reference. Time dilation is the lengthening of the time interval between two occasions for an observer in an inertial frame that is moving with respect to the rest frame of the events (in which the events happen at the same location).

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To quantitatively compare the time measurements in the two inertial frames, we can relate the distances to each other, then express each distance in regards to the time of travel (respectively either Δt or Δτ) of the pulse in the corresponding reference frame. The resulting formula can then be resolved for Δt in terms of Δτ.

###### Mass-Energy Relation

According to the special theory of relativity, mass and energy are different physical amounts but are inter-convertible. One of the most well-known equations in mathematics originates from special relativity. The formula E = mc2 shows “energy equates to mass times the speed of light squared.” It reveals that energy (E) and mass (m) are interchangeable; they are different types of the same thing. If the mass is somehow absolutely converted into energy, it likewise demonstrates how much energy would live inside that mass: rather a lot.

This equation also reveals that mass increases with speed, which effectively puts a speed limit on how fast things can move in the universe. The speed of light (c) is the fastest speed at which an object can travel in a vacuum. As an object moves, its mass likewise increases. Near the speed of light, the mass is so high that it reaches infinity, and would require unlimited energy to move it, hence topping how quickly an object can move. The only factor light moves at the speed it does is since photons, the quantum particles that comprise light, have a mass of zero.