Difference Between Relativity and Special Relativity

Relativity vs Special Relativity
 

Albert Einstein proposed the special theory of relativity in 1905. Later he proposed the general theory of relativity in 1916. These two theories became the foundation stones for the modern physics. The theory of relativity describes the behavior of matter when the velocity of it reaches the speed of light. The basic principle behind the theory of relativity is the limiting velocity of natural space as speed of light. A proper understanding in these theories is required as they are used in many fields such as nuclear physics, astronomy, cosmology and many more. In this article, we are going to discuss what relativity and special relativity are, their underlying principles, their similarities, and finally the differences between relativity and special relativity

What is Special Theory of Relativity?

Special relativity, or more precisely said, special theory of relativity was proposed by Albert Einstein is 1905. The accepted dynamics at that time were the Newtonian mechanics. The special theory of relativity explained some of the observations that could not be described using classical mechanics. To understand the special theory of relativity properly, one must first understand the concept of an inertial frame of reference. An inertial frame is a frame of reference, which is not accelerating to a predefined inertial frame. The inertial frame defined is the sun or the earth. It is important to note that all inertial frames only show rectilinear motions with respect to other inertial frames. None of the inertial frame is special. The special theory of relativity only deals with the inertial frames. Even though we cannot, even remotely, understand the special theory of relativity using a few lines there are some useful concepts, which can be helpful in describing the length contraction and time dilation. The base of special relativity is that no objects, which are moving in inertial frames, can have relative velocities greater than the speed of light.

What is Theory of Relativity?

The theory of relativity is the combination of the general theory of relativity and the special theory of relativity. The general theory of relativity basically deals with gravity. From a combination of the special theory of relativity and Newton’s law of universal gravitation, the general theory of relativity describes gravity as a curvature in the space-time continuum. In both the general and special theories of relativity, time is not an absolute quantity. Time dilation and length contraction are observed in such systems. The time dilation and length contraction are only effective if the object is moving with a velocity comparable with the velocity of light with respect to the observer.