Re: cosmology and quantum gravity

["Glenn A. Carlson" <gcarlson@MAIL.WIN.ORG>]

I agree with Mr. Rauber.  If the "gravitational effect" referred to by
Mr. Uretsky is simply the "blowing up" of the metric at the event
horizon, I question calling this coordinate singularity a
"gravitational effect."  As Mr. Rauber correctly points out, "there
are no *physical* effects that blow up at the event horizon."
[Emphasis added.]  Gravity is physical.  The coordinate singularity is
not; it's purely mathematical.

Perhaps, Mr. Uretsky can clarify what is the "gravitational effect" to
which he refers.  Is it physical or mathematical?

Glenn A. Carlson, P.E.
gcarlson@mail.win.org

> Subject: Re: cosmology and quantum gravity
> Date: Fri, 28 Apr 2000 14:48:25 -0500
> From: Jack Uretsky <jlu@HEP.ANL.GOV>

> In the
> usual metric, the gravitational effects get larger and larger as we
> approach the black hole until they blow up at the horizon, where there is
> a coordinate singularity.


> Subject: Re: cosmology and quantum gravity
>   Date: Fri, 28 Apr 2000 17:18:42 -0500
>   From: Joel Rauber <Joel_Rauber@SDSTATE.EDU>
>
> I must reiterate, there are no physical effects that blow up at the
> event horizon of a Schwarzchild black hole, at least in the usual physics
> sense of the words "blow up", which I interpret as loose language for
> diverging to infinity.