Einstein's Special Theory of Relativity

Introduction

Relativity is a widely used term. It is generally used to describe everything from the comical version of E = mc2 to concepts about time travel. Here, we are referring to the theory called the Special Relativity which was first understood by Einstein. It is a theory which enables the human mind to understand the possible actions of the universe. The theory is divided into two parts, the special, and the general. In each part, there is a certain limit to which it explains and helps to comprehend. In the special, Einstein explains ways of understanding the atom and other small objects, while the general is designed for the study of large objects, such as planets.

Analysis

Einstein published his special theory in 1905 and his general theory in 1916. The special theory applies when no accelerations are involved and its effects become noticeable near the speed of light. The general theory applies when accelerations are involved and in the presence of strong gravitational fields. It explains gravity in terms of the curvature of four dimensional space-time(Will, pp 134-78). In Einstein's Special Theory of Relativity, he laid down two postulates (Will, pp 134-78):

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

2.The speed of light through a vacuum (300,000,000 m/s or 186,000 mi/sec) is constant as observed by any observer, moving or stationary.

Principle of Equivalence

General relativity is based on the principle of equivalence. The two statements of this principle are logically equivalent; either statement can be used to prove the other. One statement relates to the concept of mass. Mass enters into Newton's second law, which states that the force needed to accelerate an object is proportional to its mass. This mass, the object's resistance to changing its velocity, is the inertial mass. Mass also enters into Newton's law of gravity. The gravitational force acting between two objects is proportional to their masses. This mass is the gravitational mass (Aczel,pp 120-178).

Is the inertial mass the same as the gravitational mass? Newton assumed that they were. Considering the question before concluding that they were, led Einstein to the general theory. The principle of equivalence states that the inertial mass equals the gravitational mass(Peterson,pp. 376-378).

From this statement, it is possible to prove the other statement of this principle: Inertial forces are indistinguishable from gravitational forces. An inertial force is the apparent force felt when in ...