From: utzoo!decvax!cca!JGA@MIT-MC@sri-unix Newsgroups: net.physics Title: weighty problems Article-I.D.: sri-unix.3167 Posted: Wed Sep 8 09:17:57 1982 Received: Thu Sep 9 03:16:59 1982 From: John G. AspinallThe question of "do gravitons escape from a black hole" brings another related question to mind. Since charge is conserved also, when you drop an object into a black hole, could we not ask the same question about virtual photons, which are considered to carry the electric field? We all "know" that real photons don't escape (tunneling aside) from the black hole, but apparently virtual ones do. Perhaps the gravitons that carry the gravitational field behave analagously. As an aside to the questions about radiation - the spectrum is determined by the acceleration of the charge. Synchrotron radiation has a characteristic spectrum because the acceleration is the circular motion of a charge in a magnetic field. But a particle dropping into a black hole also feels gravitational acceleration. So I suspect there's very little you could see from a spectrum - it'd be pretty smeared. John Aspinall.