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Gravitational force on observed particle?

  1. Feb 15, 2010 #1
    Is there any experimental difference in gravitational force for a non-observed particle versus an observed particle in a gravitational field? Basically my question is if they fall with the same acceleration?

    The observed particle is observed the entire fall, but both the observed and the non-observed particles are detected at some given distance further down at bottom. (Probably an average of all tests in the non-observed particle case is needed in order to compare it to the observed one) The situation might be similar for electromagnetic waves.

    Is there any quantum gravity theory that suggests that they should not fall with the same acceleration?
  2. jcsd
  3. Feb 15, 2010 #2
    It's problematic to arrange a proper control in this case because your measurement of the observed particle will change its motional state. Measurement induces a back-action on the particle.
  4. Feb 16, 2010 #3
    Thank you for your answer, I see the problem. Is the gravitational attraction of a single particle that is observed as one would expect from classical physics (eg Newtonian gravity)? (Has it been proven experimentally?)
  5. Feb 16, 2010 #4
  6. Feb 16, 2010 #5

    Vanadium 50

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    Yes, it's been done with interference of neutrons. Which also answers your first question, I suppose.
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