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Path: utzoo!watmath!clyde!burl!hou3c!hocda!houxm!ihnp4!ihuxr!pem1a
From: pem1a@ihuxr.UUCP (Tom Portegys)
Newsgroups: net.physics
Subject: Light from black holes, question
Message-ID: <1103@ihuxr.UUCP>
Date: Wed, 30-May-84 17:54:41 EDT
Article-I.D.: ihuxr.1103
Posted: Wed May 30 17:54:41 1984
Date-Received: Sat, 2-Jun-84 07:43:38 EDT
Organization: AT&T Bell Labs, Naperville, IL
Lines: 21


This newsgroup has been good reading lately thanks to a few
"Mr. Wizards".

I have a question.  I understand that black holes are black because
light cannot escape them.  I am wondering about the meaning of
this.  Does this mean that:

(1) No photons at all escape.  (Someone asked about gravitons escaping
a black hole recently.  This would seem related).

(2) All photons are red-shifted until they have no energy left. Only
these escape (are there such things?).

(3) The speed of light in a black hole is zero.

Excuse these if they seem crazy or ignorant.  I am both.

                         Tom Portegys
                         Bell Labs, Naperville, Ill.
                         ihuxr!pem1a or ihlpg!portegys