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A comment on Why Feynman Diagrams Are So Important. Parent comment

Re:Why Feynman Diagrams Are So Important by madengr on Thursday July 07, 2016 @09:42AM (#12049225)
Yes, I would think. Gravity warps space, and light just follows a line in space, which is a curve in space-time. But since gravity can affect light, does light (energy) affect gravity?
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Re:Why Feynman Diagrams Are So Important by auntienomen on Thursday July 07, 2016 @10:10AM (#12049392)
Yes. The gravitational field couples to any energy; it doesn't care what the source is. Light carries energy, so the gravitational field responds to it.
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Re:Why Feynman Diagrams Are So Important by egjerlow on Thursday July 07, 2016 @05:10PM (#12052106)
More formally, a photon field contributes to the so-called stress-energy tensor,which acts as the 'source' of gravity in the Einstein equations, thus affecting gravity, as you say.
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Re:Why Feynman Diagrams Are So Important by OscarCunningham on Thursday July 07, 2016 @11:42AM (#12050004)
Yeah, in physics if A affects B then B always affects A. This idea was first formalised as Newton's Third Law.
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