Question

What is "special" about the special theory of relativity? It deals with motion at constant velocity and accelerated motion but excludes all other effects; in particular, it excludes gravity.

Answer 1

The 'special' in special theory of relativity denotes its scope limited to inertial frames moving at constant velocity and excludes gravity, while general relativity encompasses all motions including gravity.

Step-by-step explanation:

The term "special" in the special theory of relativity refers to the theory's application to only specific conditions, specifically cases involving inertial frames of reference or observers that move at constant, unaccelerated velocities relative to each other. It contrasts with general relativity, which extends the ideas to include gravity and accelerated motion. The special theory of relativity is founded on two postulates proposed by Albert Einstein: the first states that the laws of physics are identical in all inertial frames of reference, and the second postulates that the speed of light in a vacuum is constant, regardless of the relative motion of its source or the observer.

Answer 2

Step-by-step explanation:

The reason it is called the special theory of relativity is because it's a special case of the general theory of relativity. SR deals with uniform motion, where there is no acceleration. Spacetime in special relativity is flat, with no gravity or curvature. It is a spacetime with no gravity. On the other hand, GR deals with accelerating reference frames and curved spacetime.