Hello, I can answer some basic questions about GR, but I don't teach it, and I am not proficient in it. Yesterday a student asked a question that I felt I couldn't do justice to. Can you help? I had the student email the question so I could ask around. So far I haven't gotten any useful answers from friends, so I'm trying here. Another question, which he didn't include in the email was: Would a charge in gravitational orbit radiate? If it did, then I would think the equivalence principle would be false (an inertial observer would notice an anomolous force on charged particles), so I told him no. But he followed up by pointing out that even two neutral bodies spiral into each other in finite time. If they can lose energy gravitationally, why not electromagnetically? I said, (and warned that I was probably incorrect and would double check), that if gravity effectively provided a drag force that sprialled them together, that locally you could not detect any 'anomolous force' since it would act on all particles in proportion to their mass and therefore the equivalence principle does not forbid this while it would for the electromagnetic case. Please help. Since my responses are most likely incorrect.