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Electrodynamic checks of the equivalence principle

  1. Feb 6, 2009 #1

    I would like to know if there are experimental tests of the Equivalence Principle in the realm of electrodynamics. The book by http://books.google.com/books?id=Bh...eriment+in+Gravitational+Physics&lr=#PPP1,M1" contains a lot of material about the equivalence principle. The Einstein Equivalence Principle is of course defined and it clearly extends the weak equivalence principle to any possible experiments in accelerated frames or in the presence of a gravitational field.

    However, I could not find any description of an experimental test of the EEP in the domain of electrodynamics.

    Would you know some?

    Last edited by a moderator: Apr 24, 2017
  2. jcsd
  3. Feb 6, 2009 #2


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    The very first experimental test of the equivalence principle was in the field of electrodynamics, i.e. the effect of gravity on light. Einstein predicted that gravity would bend light, and this was tested in a famous experiment by Eddington. Another effect on electrodynamics is the gravitational redshift of light. This was tested very precisely using the Mossbauer effect in 1959. These same effects are also predicted by quantum electrodynamics in exact agreement with general relativity, and quantum electrodynamics is the most accurately tested theory we currently have, so you can consider this consistency also as a check of the equivalence principle.
    Last edited: Feb 6, 2009
  4. Feb 6, 2009 #3
    Thanks dx,

    Indeed light is the first example!
    However, I was more thinking to charged particles.

    I found a direct experiment on the free fall of electrons: http://adsabs.harvard.edu/abs/1967PhRvL..19.1049W".
    See also: http://books.google.com/books?id=8yAssyaLq2sC&pg=PA264&lpg=PA264&dq=%22Experimental+comparison+of+the+gravitational+force+on+freely+falling+electrons+and+metallic+electrons%22&source=web&ots=IXvQQpZD7A&sig=E6kaONtu4GO6qFIcNESlAkdc7LY&hl=en&ei=CRCMSZCLENKX_gaJvbTBDA&sa=X&oi=book_result&resnum=5&ct=result#PPR8,M1" [Broken]
    I only read the abstract, but it looks quite interresting although also rather limited and unprecise.

    But since atoms are made of charged particles, would there be something to look at in atomic physics?

    Thanks already.
    Last edited by a moderator: May 4, 2017
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