Re: Time dilation, spaghetti and black holes

On Sun, 18 Dec 2005 15:17:47 -0000, Gerry Quinn wrote:

> In article <1w0zkzuv7rai9.1r47eols5ii07$.dlg@xxxxxxxxxx>,
> warlocke@xxxxxxxxxxxx says...
>
>> A year or more of Scientific American just fell into place. A black hole
>> has to be a black /shell/ -- anything that falls into it has to go faster
>> than light to get either out /or/ further in. So all that stuff just lurks
>> at the event horizon.
>
> Many would agree with you, but not those devoted to general relativity.
> Their claim is that the singularity you have identified is a false
> 'coordinate' singularity. And indeed the equations of general
> relativity can be used to describe spacetimes in which object
> trajectories can cross the horizon.
>
> This comes at some considerable costs to common sense, such as the
> conflicts with quantum theory and thermodynamics, a completely
> incomprehensible central singularity, and no bright line between this
> and ever more exotic and unlikely spacetime topologies. Costs they
> have tended to pooh-pooh.
>
> The tide is against them these days, though...
>
> - Gerry Quinn

If the Universe made sense there would be no work for theoretical
physicists :-)

I'm not totally sure the phrase "physical meaning of a black hole event
horizon" is denotative. The best that can be done is analogies, and as Col.
duBois remarked, analogy is always suspect. But it's fun to read the
articles and do some uninformed speculation.

Regards,
Ric
.

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