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The exchange particle for gravity: the graviton?

  1. Jun 11, 2004 #1
    As far as I can see, the exchange particle involved in gravitational forces is the graviton. However, in the markscheme for both the original and revised EDEXCEL A-Level Physics PHY3 Topics Paper (topic C) it states that it is the photon.
    Which is correct, or are both correct? Why is there this difference?

    The question states: "List the other fundamental interactions. Circle the one for which the photon is the exchange particle."
    The markscheme says Weak, Electromagnetic, Gravitational, Gravitational Circled.

    I thought the photon was exchanged between two electrons interacting, which is what the Letts revision textbook says. Is this in fact a gravitational interaction? Surely its electrostatic!

    Im guessing I should learn it to be the photon, but this seems strange as most other sources I've found say its the graviton - including the revision textbook which covers the EDEXCEL syllabus. :confused:

    Can anyone help? :cry: Thanks! :biggrin:
  2. jcsd
  3. Jun 11, 2004 #2


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    Your confusion is justified.

    Gravitons, if they exist, is the hypthetical carrier of the gravitational interaction. Photons are the carrier of electromagnetic interactions. If your test is indicating that gravity is carrried by photons, then this is wrong. You should alert someone of authority about this error. If you get nowhere, or they simply dismiss you, write back.

  4. Jun 11, 2004 #3
    The specification for the topic doesn't mention the graviton at all. However it does still seem incorrect to use the photon instead. I have contacted EDEXCEL regarding this matter.
    Thanks for the help :)
  5. Jun 11, 2004 #4


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    And what about Weak, is that circled too? Certainly the statement "The photon is the exchange particle for the Weak interaction" is false as it stands.
  6. Jun 11, 2004 #5
    Only gravitational is circled.
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