IS THERE an ether drift? In these days when the most advanced science seems based on the premise that there is no ether, that question might seem silly to some. Nevertheless, it is asked in all seriousness.
At one time not so long ago science based much of its theory on an "imponderable medium" pervading all space, which was supposed to offer NO RESISTANCE whatever to the passage of matter through it. It was supposed to be stationary in space, so that by relating all movement to the stationary ether we would have more or less absolute motion. Thus, the Earth, according to this theory on the ether, was moving at least many miles per second THROUGH the ether.
This theory was accepted by scientists and believed to be true. So when Michelson and Morley performed their famous experiments on ether drift they did it with confidence that they would be able to measure the velocity of the ether. No one was more surprised than they when their results proved negative consistently. Nevertheless, being honest scientists, they had to accept their experimental data. THE EARTH DID NOT MOVE THROUGH THE ETHER.
Two different types of setups were used in these experiments. Both were essentially the same in principle. The one, now famous and described in most advanced physics books as well as in THE MYSTERIOUS UNIVERSE, by Jeans, floated in a pool of mercury, so that the paths of light WERE AT ALL TIMES IN THE HORIZONTAL PLANE. The other, reported by Michelson in the AMERICAN JOURNAL OF SCIENCE, Series 4, Volume 3, 475-78, year 1897, was set up in a fixed frame so that NOTHING ABOUT IT MOVED RELATIVE TO THE EARTH. The rotation of the Earth itself was supposed to turn the apparatus in the ether stream.
These two experiments were done many times and always gave negative results, so the conclusion had to be accepted that THERE IS NO STATIONARY ETHER THROUGH WHICH THE EARTH MOVES.
It is one of the peculiarities of the human mind that a specific statement can be used to generalize far beyond what it originally implied. Today the former conclusion of the ether drift experiment has been subtly altered to state that there is no move-
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