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Ether Ether everywhere.

  1. Nov 18, 2004 #1
    It is known that the concept of Ether was present in the whole of the Universe was started by Maxwell for representing the material medium for the travel of the electromagnetic waves.
    Question 1: Why Ether and not any other substance i.e., what are the special properties of the Ether?
    Question 2: How Einstein`s basic assumption in the Special theory of Relativity proved that if Ether exist it should in Absolute frame of Reference (theoretically) and was disproved by Michelson and Morley(experimentally)?
    Thanking you in advance.
  2. jcsd
  3. Nov 18, 2004 #2
    1. Wave motion is the composite motion of particles, thus for em waves to exist,
    a particle medium is required to carry them. The Ether was proposed as such a medium. Why the Ether if so many atoms are available to carry em wave motion? Probably to explain the odd fact that when they created a "vacuum" in a lab, em waves still propagated. So their "Ether" can be thought of as a particle medium whose particles are so small that lab techniques could mistake it as a vacuum.

    2. The ether, if it existed, should behave like a pool of water inside a 747. The pool of water would seem motionless and when a nickel dropped in it, the ripples emanating spherically outward, just like a nickel dropped in a pool in someone's backyard. In other words, the Ether in which the MM experiment was carried out is stationary with the Earth so that you couldn't detect any "Ether" winds. Einstein's Special Relativity and the MM experiment then did not disprove the existence of an Ether but only that if there was, the Earth and other masses carry their own Ether so that you can't tell your motion through it because it is stationary relative to you. Stationary however is very different from being superfluous, which was what many believers in SR called it. The Mayflower stationary in a still Atlantic Ocean for example does not make the Atlantic Ocean superfluous. Nor does a Honda Civic stopped at a traffic light make the "stationary" pavement beneath it superfluous.

    A more correct way to describe the Ether then is that it is any particle medium and an alternative way of interpreting em waves' propagation through a vacuum, to make it consistent with the notion of wave motion being a composite of particle motion, is that the vacuum generated in labs is not a true vacuum but are composed of tiny "ether particles".
    Last edited: Nov 18, 2004
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