Mechanics / Electrodynamics
July 20, 2018
Albert A. Michelson proposed the idea to compare the path lengths of two split rays of light that recombine after traveling forward and backward along the two arms of his interferometer. The transmitted ray travels in the same direction as that of the velocity of the Earth’s orbit around the Sun and the reflected ray perpendicular to it. Michelson and Morley consider that the two split rays, at one point on the beam splitter, intercepts the same point later at two different instances and concurrently make the rays coincide along the interference path. These experimental objectives are not realistic. Split rays at one point on the beam splitter that intercept the same point later at two different instances cannot generate coinciding rays. Alternatively, to have the interfering rays coincide, the rays that interfere at one point on the beam splitter have to originate from different points.