June 5, 2018
Counterintuitive, Einstein, Feynman, Brian Cox, Lorentz, Light-clock, Ladder in Barn Paradox, Twins' Paradox, speed of light, simultaneity, reciprocity, time dilation, length contraction, inertial reference frames, acceleration, constant motion
Einstein maintained that the laws of physics are the same for all observers in uniform motion, relative to one another, and that a frame of reference is one in which a body remains at rest or moves with constant linear velocity unless acted upon by forces.
A reference frame also has the ability to determine measurements of the time of events using a 'clock', and to determine differences between the 'time' circumstances of two observers.
At the time when Einstein was postulating these considerations, he was under the misapprehension that the Universe was static. He, therefore, was able to hypothesise that the laws of physics are identical in all inertial systems, that is; in non-accelerating frames. So how do we view these principles now we have the understanding that the Universe is accelerating, and, therefore, absolutely everything must be accelerating along with it?