Re: GR THEORY IS NOT EVEN FALSE!

On May 3, 5:03 pm, Tom Roberts <tjroberts...@xxxxxxxxxxxxx> wrote:
mluttg...@xxxxxxxxxx wrote:
According to the paper astro-ph/0509758,
when matter falls through the event horizon of
a black hole, nothing is statistically observed.

No local observation can detect when an observer crosses an event
horizon. So this goes much deeper than "statistical".

You also said that "a black hole is a region in spacetime,
not a material object".

Yes.

I am not sure to understand what you mean by
"not a material object", as a black holes have mass

A black hole behaves AS IF it has mass. It's not clear whether the usual
meaning of "to have" applies. But this is mere words, and for all
practical purposes a black hole has mass. But the region near the
horizon is completely devoid of any of that mass; insofar as one can
describe it with the usual words, the "mass" must be concentrated "in"
the singularity (quoted words have bent meanings).

Otoh, according to Ramesh Narayan
(astro-ph/0310692) -and other BH specialists-,
"A black hole represents the ultimate victory of gravity,
where all the mass in the object collapses down to a
“singularity”, a true geometrical point (at least within
classical physics)."

Yes.

As for me, quantum theory is classical physics.

You cannot apply YOUR meanings of words to what someone else wrote. THEY
clearly used the word "classical" to mean NON-QUANTUM. This is the usual
meaning of the phrase "classical physics" today.

As quantum mechanics is "as well-supported by
mathematics and experimental evidence as general
relativity, and it does not allow objects to have zero
size -so quantum mechanics says the center of a black
hole is not a singularity but just a very large mass
compressed into the smallest possible volume."
(cf.http://en.wikipedia.org/wiki/Black_hole#Sizes).

GR and QM are inconsistent, and so it's no surprise that their
descriptions of a given phenomenon are in conflict.

That said, GR breaks down in the region near the singularity, and nobody
expects it to accurately describe what happens there. Neither does QM
apply accurately there. We need a theory of quantum gravity to have much
hope of understanding this....

Let's assume that BH diameters correspond to
the Plank's length.

No! The usual meaning of "black hole radius" is the "radius" of its
event horizon, not a tiny region near its singularity. For a solar mass
BH that is a kilometer or so, and for supermassive black holes observed
at the centers of galaxies it can be on the order of an astronomical
unit (radius of the earth's orbit).

One could consider that a BH is
an exotic particle, that could be called a 'bholon', from
which nothing can escape, as its surface gravitational
potential is much too big (Let's forget Hawking
radiation!).

Normally when we discuss "particle", we mean something very small, not
millions of kilometers in diameter!

At some distance R from the BH center, which is
a function of the BH mass, exists an "event horizon".
For an observer at R, an incoming light would appear
to have an infinite frequency f, according to a well
known GR formula.

No. You are assuming that observer is at rest relative to the BH, but
that is not possible. A timelike observer never measures "infinite
blueshift".

But there is no clear reason why that light would not
continue its trip to the 'bholon' itself, and its infinite
(from hf/c^2) mass "merge" with that of the BH.
Conclusively, the mass of the BH would immediately
become infinite! All BH would have an infinite mass!
This is not confirmed by observations, for instance of
X-ray binaries.

Your argument completely ignores the ACTUAL structure of black hole
manifolds in GR. You clearly need to study this, as you GUESSES are
simply wrong.

The obvious conclusion is that the GR formula is
'physically' wrong.

No. The OBVIOUS conclusion is that you do not understand how GR applies
to black holes. Your "sound bite" approach to physics is inadequate, and
you must STUDY the relevant physics.

Tom Roberts

Thank you for your precisions, which exclude black holes
from my reasoning.

But other strange objects could cast doubt on the
validity of GR:

Some stars could have a radius R,
which is smaller than their Schwarzschild
radius Rs, for instance the hypothetical
preon stars (which, btw, are no more
hypothetical than black holes).

As, according to GR, incoming light would
have infinite frequency -and thus energy-
relative to Rs, the mass of preon stars
would become infinite when the same light
reaches R.

As this is physically senseless, one has
to conclude that GR has here a big problem.

Marcel Luttgens

.

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