NetNews Usenet Archive 1992 #16/NN_1992_16.iso/spool/sci/astro/8401

Internet Message Format | 1992-07-28 | 1.9 KB

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From: [e-mail] (Matthew P Wiener)
Newsgroups: sci.astro
Subject: Re: On the formation of black holes
Message-ID: <[e-mail]>
Date: 28 Jul 92 12:59:58 GMT
References: <[e-mail]> <[e-mail]>
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Reply-To: [e-mail] (Matthew P Wiener)
Organization: The Wistar Institute of Anatomy and Biology
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In-reply-to: [e-mail] (Warren G. Anderson)

In article <[e-mail]>, anderson@fermi (Warren G. Anderson) writes:
>Thus, there will never be a *last* outgoing null surface that the test particle
>can emit on; every outgoing null surface that a stationary observer passes
>through can contain an emission from the test particle.

You're right.  I still remember a respected relativist claiming the black-
ness can be explained purely geometrically, which is why I assert it with
such confidence, although I take credit for inventing the wrong argument.

Second try below.

>> They explicitly say that an arbitrary low amount of possible radiation
>> omitted holds even in the continuum approximation--discretization of
>> emission only accelerates this part of the process.

>I agree, the classical field can be made arbitrarily but finitely small
>by having the classical observer look at a suuficiently great proper time.
>However, as long as the field is classical, I maintain that it can affect the
>stationary observer for an infinite amount of the observers proper time before
>it becomes infinitesimal.

Earlier we agreed to ignore the horizon expanding as the object falls in,
as a simplification.  If we don't, doesn't this cut off the emissions?
--
-Matthew P Wiener ([e-mail])