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Creationism and other doctrines. Was Mindforth

Alex McDonald alex_mcd at btopenworld.com
Wed Dec 18 17:33:49 EST 2002

"John R. Strohm" <strohm at airmail.net> wrote in message
news:D1A854DAF441903C.E66E26A07BFE37EE.9281BCC976EA22C3 at lp.airnews.net...
> Dennis, what you are missing is that you are in fact expressing "faith"
> you express the concept of "observable" and "repeatable".  I.e., you are
> expressing FAITH that an observable, repeatable phenomenon is in FACT both
> observable and repeatable.

Your observer is obviously human, as an act of faith is involved. What of
non-human obervers whose state is changed by the act of observing something?
For instance, a geiger counter?

> Dr. Stephen Hawking showed, many years ago, that existing theory allows
> the existence of regions of space-time that are flat-out unobservable.  We
> DO NOT and CANNOT know what is happening in those regions.

The laws of physics appear to be the same whereever we look in the
observable universe. There may be parts of the universe that are
unobservable and that are not black holes. But as such a part has (by
definition) no effect upon us, any theory about the nature of physical law
there is untestable, and is hence unscientific.

But for black holes, this is not true. We know, for instance, the mass, the
spin and the entropy inside a black hole -- without looking inside. And some
testable theories (presently untestable give the limitations of technology,
but as they are testable they are scientific) claim that physical law is the
same inside a black hole as outside, right up to the point of the
singularity where quantum gravity takes over.

> He then went on
> to show that the boundaries of those regions were uncertain, and that
> phenomena could emerge from inside the unobservable region.

Again, not true. The "phenomena" are virtual particle pairs formed by vacuum
fluctuations both outside and inside the black hole; one of the virtual pair
disappears into the hole and the second particle, now real, can escape -- as
observed by someone stationery and outside the hole (technically, an
accelerated observer, i.e. you and me). Nothing "emerges" from inside a
black hole.

> The executive summary is this: a black hole isn't completely black. It
> leaks, and furthermore it can leak ANYTHING AT ALL.

No. It doesn't leak, it radiates from the event horizon...

> According to Dr. Jerry
> Pournelle, who attended Dr. Hawking's presentation at Caltech (on
> from Dr. Robert Forward), Hawking finished his talk by saying "Of course,
> might be a while before the black hole emitted one of the people in this
> room..."

... and it doesn't leak people either. There is as much chance of a black
hole radiating a physicist as there is a physicist materialising in the
corner of your room. Black holes (tiny black holes excepted) radiate
incredibly slowly. A 3-sun mass black hole has a surface temperature from
"accelerated radiation" of about 10pow-8 deg K. Hence Hawking's statement.

> Hawking's talk was entitled "The Breakdown of Physics in the Region of
> Space-Time Discontinuities", or some such.  His second slide was the same
> title, except he'd crossed out the word "Physics" and substituted
> "Physicists".

For an excellent layman's description of black holes and their physics, you
may care to read Kip S Thorne's "Black Holes & Time Warps" (1994). You will
find much to help you understand why your argument is not correct, and why
Hawking is given to making funny and witty observations.

Alex McDonald

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