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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

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