Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site wdl1.UUCP Path: utzoo!linus!philabs!cmcl2!seismo!lll-crg!dual!qantel!hplabs!hpda!fortune!wdl1!jrm From: jrm@wdl1.UUCP Newsgroups: net.physics Subject: A Queation Regarding Black Holes Message-ID: <625@wdl1.UUCP> Date: Wed, 7-Aug-85 15:24:20 EDT Article-I.D.: wdl1.625 Posted: Wed Aug 7 15:24:20 1985 Date-Received: Mon, 12-Aug-85 04:55:30 EDT Sender: notes@wdl1.UUCP Organization: Ford Aerospace, Western Development Laboratories Lines: 24 Nf-ID: #N:wdl1:5100002:000:1055 Nf-From: wdl1!jrm Aug 7 10:54:00 1985 /***** wdl1:net.astro.expert / jrm / 1:03 pm Aug 6, 1985*/ A common science fiction theme is that of a ship orbiting a black hole under intense gravitational and tidal forces. Another is a ship falling into a black hole (usually with discussion of the relativistic effects). However.... By definition, the gravitational feild of a black hole is so intense that not even light or other wavicles with velocity c can escape. My understanding is that gravity propagates with velocity c. (I believe this has been proven. Correct?) Does this not imply that, at least as far as the outside universe is concerned, the black hole has no gravitational feild? Further, since everything with velocity <=c is kept within the black hole, does this not mean that the black hole is undetectable? Even to the extent that you could pass through one or it could pass through you and neither would know anything had happened? Does quantum mechanics affect this? (In terms of "things" escaping from the black hole.) jrm@ford-wdl1 /* ---------- */