What is the aim and the conclusion of michelsen-morely experiment?
Answers
The main objective of the Michelson-Morley experiment was to check for the presence of the 'luminiferous ' aether. A substance that had to possess millions of time the rigidity of steel in order to accommodate transverse waves travelling at a speed of approx. 2.99×1052.99×10^5 Km/s and at the same time had to be flexible enough to allow for the passage of planets through it and was also transparent and completely undetectable to the ordinary senses. A tall order to fulfill! The idea was to measure the velocity of the earth with respect to the aether. If the earth were moving through the stationary aether with a uniform velocity and if a beam of light were sent from the source in the direction of the motion of the earth, then it would be travelling in opposition to the aether and should take more time to reach its destination than if sent in the opposite direction. The time difference between the two measurements could then be measured and the velocity of the earth with respect to the aether determined. Unfortunately, at the end of the experiment there was nothing to measure! The Michelson & Morley experiment has been called the most important failed experiment in History. In retrospect, this judgment may have been a little hasty. Consider what they had set out to find: A medium that was millions of times more rigid than steel, but was completely transparent and pliable enough for the planets to move through without hindrance! It can hardly have come as a surprise when such a medium failed to be detected. Yet so important was this concept of an aether to science that several scientists, most important amongst them, the highly respected Dutch Scientist Hendrik Lorentz, went to incredible lengths to show why the Michelson & Morley experiments had failed to detect the aether; among his many ideas were time dilation and length contraction known today as Lorentz transformations and adopted more or less unchanged by Einstein for his special theory of relativity. The point to stress here is not that Einstein adapted Lorentz's equations for his own use but that Scientists thought the aether important enough to pursue improbably theories in search of. In the end reason could not sustain the idea that a medium or substance that possessed millions of times the rigidity of steel, yet was completely permeable to matter and completely invisible could possibly exist. When, therefore, the suggestion was put forward that electromagnetic radiation did not require a medium to propagate, it was welcomed with a sense of relief.
One result of Newton's theory of gravity was that according to the theory, stars should attract each other and therefore could not remain as fixed points in the sky as had been conjectured for thousands of years. Newton, himself was very worried by the lack of absolute position, or absolute space, that was implicit in his theory that the stars moved.