I was in discussion about black holes with a friend, and I seem to have found a big misconception. I apologize for asking such a trivial question, but I'm not certain even as to how to precisely ask it. I've waited a long time to learn about GR as it's a bit intimidating to me.(adsbygoogle = window.adsbygoogle || []).push({});

Me: A static electromagnetic (I realize that if the field is static it's either one or the other) field will not affect the propagation of photons, similarly the propagation of gravity is unaffected by gravity."

Him: This part is wrong.

Gravity curves space-time itself. Gravitons, just like photons, travel along geodesics of the space-time. All massless particles do. This means that the graviton will follow the same trajectory as light. That means, it will be affected by gravity.

I'm not familiar enough with theories including gravitons to make any statements concerning them, but it is it not true that changes in gravity propagate at c regardless of its own effects? Would his statements mean that gravity is capable of trapping itself?

I guess my problems arise from my assumption that gravity can't be viewed as a force, but only as warp of spacetime. If gravity waves, quantized or not, are not allowed to leave a black hole, how would it have a measurable angular momentum?

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# Trivial question about gravity affecting itself

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