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Can virtual produce anti-gravity?

  1. Jun 25, 2005 #1
    Perhaps it is a stupid question, but really confuses me.
    In QFT, virtual particles can be produced from vacuum, say, (M,0,0,0) and (-M,0,0,0)
    In Einstein's theory, if we consider the (-M,0,0,0) virtual particle, make it's energy-momentum tensor and solve the Einstein equation, and take the limit of weak field, we find the potential it produces for other real particles is positive, so it gives a exculsive force.
    Is it right? if so, can the negative-energy particle fall into the blackhole? because if the negative energy particle has anti-gravity, it can never go into a place that have infinity high potential energy.

    Thank you!
     
  2. jcsd
  3. Jun 27, 2005 #2

    hellfire

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    When a particle-antiparticle pair is created from vacuum both have positive energies. However, there is a heuristic way to explanation Hawking radiatio invoking negative energies viewed by observers at infinity (I remember I read something in Schutz). Anyway, consider a particle of negative energy at the event horizon. The force between the black hole and this particle would be repulsive. However, since the particle has a negative (inertial) mass, it would accelerate in the contrary direction to the force and it would fall into the black hole.
     
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