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Equivalence Principle precision

  1. Jun 16, 2011 #1
    I found 2 tables describing raising precision in experiments performed to investigate Equivalence Principle:
    http://en.wikipedia.org/wiki/Equivalence_principle#Tests_of_the_weak_equivalence_principle
    http://en.wikipedia.org/wiki/Hughes–Drever_experiment#Modern_experiments

    I can't understand how to compare the two tables: is that possible? If second one is expressed in GeV, in which unit of measure is the first expressed? Is it just an adimensional ratio?
     
  2. jcsd
  3. Jun 16, 2011 #2

    Bill_K

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    Science Advisor

    Numbers in the first table are dimensionless percentages, what he calls the Eotvos parameter.
    Numbers in the second table give a fraction of a GeV, but since the mass of protons and neutrons is approximately a GeV, they may be regarded as percentages too. For the electron column you'll have to divide by the electron mass to get a percentage.
     
  4. Jun 17, 2011 #3
    Sorry but I can't yet understand.
    How can I convert second table values into ratios? By dividing by c^2?
     
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