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Thrust imparted from a photon?

  1. Sep 25, 2015 #1
    If I produced a material that neither absorbed nor reflected light. Or at least did so to an extremely miniscule amount and set it in space and hit it with light. Would there be any thrust imparted unto it?

    If so would it be significant?
    My initial thoughts would be that sense it is massless there would be no thrust. But if the particle cannot pass through the object reflect off the object or go around the object , it has to move the object. No?

    Also if light is massless and cannot be slowed let us say I take a perfect mirror and craft a box out of it and make it small enough that the inside can contain a single photon, what would happen?
  2. jcsd
  3. Sep 25, 2015 #2


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    I guess scattering is forbidden as well?
    Then it would not interact with light at all, the material is completely transparent. No thrust.
    To get thrust, it has to absorb, reflect or scatter light.

    Light is massless, but it has momentum.
    It can be slower in a medium that interacts with light.
    The photon would stay inside. In the radio-frequency range, there are good approximations to perfect mirrors - they can store electromagnetic oscillations for several seconds.
  4. Oct 7, 2015 #3


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    If the material "neither absorbed nor reflected light", where does the light go?
  5. Oct 8, 2015 #4


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    it just passes through, without an effect....
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