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Could gravity have 2 components like a photon

  1. Jul 25, 2010 #1
    could gravity have 2 components like a photon , or does gravity just have one component?
    Is a gravitational wave a self-sustaining G field .
  2. jcsd
  3. Jul 25, 2010 #2


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    Yes, linearized gravity gives rise to a gravitomagnetic field, which is like the magnetic field of a photon. So a graviton does have two components like that.

    But linearized gravity only works in relatively weak gravitational fields. It breaks down in vicinities of such objects as neutron stars and black holes.
  4. Jul 25, 2010 #3
    That's a good question, Crager.

    Gravity itself (say of a non-rotating planet) is considered to have one component and is usually referred to as the the gravito-electric field, which is analogous to a static charged sphere which only consists of an electric (electrostatic) field.

    However, (as K^2 mentinioned) according to the linearized field equations matter in motion gives rise to a gravito-magnetic field analogous to a magnetic field resulting from motion of charge. A time rate of change of the gravitoelectric field (gravity) can also give rise to a gravito-magnetic field.

    And yes, gravitational "waves" can then be considered to have two components, like EM, albeit, not predicted to be dipolar, but quadrupolar.

    Last edited: Jul 25, 2010
  5. Jul 25, 2010 #4
    interesting thanks for your answers .
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