Question

What is meant by absolute time? Why was it not noticed before the development of the special theory of relativity?

Answer 1

In kinematics, motion equations are derived using the time interval, Δt, between events. Before the concept of special theory of relativity came to be, everyone thought that the time interval, Δt, is the same for every observer, whether the observer is at rest or in motion. This is called absolute time.

However, according to Einstein, time is not absolute; that is, the time interval, Δt, depends upon the velocity of the observer

Answer 2

Absolute time is placing a number on an object or event. It would be like saying this fossil is 500,000,000 millions years old or a volcanic eruption took place 200,000 years ago. Absolute time is expressed in numbers.

Newton's assumptions were perfectly rational, considering the prevailing knowledge at the time he lived. His conclusions were absolutely revolutionary, and his work is still used on a daily basis by engineers designing everything from skateboards to spacecraft.