Re: Do you believe in black holes?


"dlzc" <dlzc1@xxxxxxx> wrote in message
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On Oct 1, 8:40 am, George Dishman <geo...@xxxxxxxxxxxxxxxxx> wrote:
On 30 Sep, 21:10, "N:dlzcD:aol T:com \(dlzc\)" <dl...@xxxxxxx> wrote:
"GeorgeDishman" <geo...@xxxxxxxxxxxxxxxxx> wrote in message
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"dlzc" <dl...@xxxxxxx> wrote in message
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On Sep 26, 8:37 am, GeorgeDishman<geo...@xxxxxxxxxxxxxxxxx>
wrote:
On 26 Sep, 14:34, "N:dlzcD:aol T:com \(dlzc\)"
<dl...@xxxxxxx> wrote:
"GeorgeDishman" <geo...@xxxxxxxxxxxxxxxxx> wrote in
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On 25 Sep, 18:14,dlzc<dl...@xxxxxxx> wrote:
....

.. in this context "information" is the quantum
numbers of the particles that entered the black
hole to provide it with its mass.

And how is it any different if the mass is located in
the "Coal Sack", speaking from QM? QM does not
care about "spacetime geometry", so I don't see
how being "within an event horizon" is any different.

I am losing why you think that is relevant to what
we are discussing. You said "'Black body radiation'
is information." but it does not contain information
in the QM sense regardless of the source of the
radiation.

OK. Let's forget the "black body" stuff.
How is mass located in the Coal Sack different from mass located in a
black hole, from any distance of 100 ly or more? We can't see
anything inside the Coal Sack either (barring improvement in
technology). Yes we can go there (eventually), but does quantum
mechanics "care" about either situation.

The matter in the coal sack consistes of particles
which conserve certain quantites for each individual
particle. The singularity in the black hole conserves
the total but the individual information is "lost", or
at least locked up in it. The Hawking radiation which
dissipates the mass is generated at the horizon, far
from the singularity so cannot carry away information
to which it has no access.

The standard "information loss problem" AIUI is that
mass falls into the hole carrying with it information.
The hole evaporates giving off only Hawking Radiation
which has a purely thermal spectrum thus carries _no_
information and hence the information is lost. That
is the background to the discussion.

The particles of which Hawking radiation is comprised is *not* limited
to photons. The "thermal energy" emission is inclusive of charged
(anti)particles, and collections of photons that are travelling non-
parallel have non-zero rest mass. From time-of-formation to time-of-
complete-evaporation, over that whole "event", I don't see that
information is lost.

How does the quantum information locked in the
singularity end up back in the universe when the
Hawking Radiation is generated at the horizon?
Whether it is phaotons or not, the numbers are
random.

How are "the field" and "the Universe" different, in
your opinion George? Einstein said "the field"
was responsible for curvature.

I would have to see the context to see which "field"
he meant, I don't know the quote. It may be just a
question of terminology, I might be using "metric"
or perhaps the means the "field equations".

"Relativity. The Special and the General Theory",
Albert Einstein, translation by John Lawson,
copyright 1961. Appendix Five "Relativity and the
Problem of Space", the subsection "The Concept
of Space in the General Theory of Relativity", last
paragraph.
<QUOTE>
Thus Descartes was not so far from the truth
when he believe he must exclude the existence
of an empty space. The notion indeed appears
absurd, as long a physical reality is seen
exclusively in ponderable bodies. It requires the
idea of the field as the representative of reality,
in combination with the general principle of
relativity, to show the true kernel of Descartes'
idea; there exists no space "empty of field".
<END QUOTE... any typos are mine>
Same appendix, subsection "The Field", 4th
paragraph
<QUOTE>
... In accordance with the historical
development of the field concept, where no
matter was available there could exist no
field. But in the first quarter of the nineteenth
it was shown the that phenomena of the
interference and motion of light could be
explained with astonishing clearness when
light was regarded as a wave-field,
completely analogous to the mechanical
vibration field in an elastic solid body. It was
thus felt necessary to intoduce a field, that
could also exist in "empty space" in the
absence of ponderable matter.
<END QUOTE... any typos are mine>
... further in this subsection, he mentions
"modifiers" to (or flavors of) the field theory...
Maxwell, aether.

Based on the balance of the text, I think the
field equations are descriptors of "the field".
But it is clear to me, "the field" is
fundamentally bonded to the "ponderable
matter" necessary to, for example, produce
diffraction.

Thanks for the detail. I read it in the opposite sense,
it says:

"It was thus felt necessary to intoduce a field, that
could also exist in "empty space" in the absence of
ponderable matter."

However, the references are primarily to the electric
and magnetic fields of Maxwell's equations.

It was stated as being the field equations of general relativity, in a
book about relativity, with a passing mention of Maxwell. Look at the
original quote in section 5, where he applies "field" to "space".

Still no problem, "field" is an attribute of space
just as colour might be an attribute of matter.
Without space, you cannot have a field. Again I
think that is perfectly clear from the quote you
provided:

"In accordance with the historical development
of the field concept, where no matter was
available there could exist no field. But in
the first quarter of the nineteenth it was
shown the that phenomena of the interference
and motion of light could be explained with
astonishing clearness when light was regarded
as a wave-field, completely analogous to the
mechanical vibration field in an elastic solid
body. It was thus felt necessary to intoduce
a field, that could also exist in 'empty space'
in the absence of ponderable matter."

You asked me "How are 'the field' and 'the Universe'
different, in your opinion George?". If I put my hand
in front of a CRT, the hairs on the back of my hand
stand up due to the electric field. The universe is
everything to the limits of observability and beyond.

If the Sun is charged, will the hairs on your hand stand up *not at
all*?

The atmosphere would act like a Faraday cage
but the ionosphere would 'stand up' in exactly
that way.

Likewise, for the Andromeda galaxy, or any distant point?
Because we have "difficulty" measuring a variance, does that mean
there isn't a connection?

There is a connection but that doesn't mean they
are synonomous. "Field" is an attribute of "space"
and matter exists as discrete entities within that
space. Those entities can affect the value of the
field and all of them together constitute the
universe. What is so hard about that David, you
seem to be looking for an argument.

You also said "Einstein said 'the field' was
responsible for curvature.". The equations say the
stress/energy tensor causes curvature but the
electric field is one possible source of energy.

... and I am asking what is the source of "that which is curved". The
equations map their own "solution space", a connection we have crafted
to mimic reality. What is the name of that which the stress/energy
tensor models?

Typical examples of stress/energy are the pressure
in a fluid and mass respectively. The name of "that
which is curved" is "the metric" and it models the
geometry of spacetime.

And we will continue to disagree. And it
cannot be experimentally disproven, since
there is no stretch of space that does not
have two bits of matter / energy either
propagating through it, or "staring" at each
other across it. Only in "models" is such
"pure" spacetime availaable.

The GR model is quite clear on the matter though,
ripples can progress through the metric without
the need for matter other than the source:

There you go again... "without the need". Maybe
English is just too imprecise.

I think it is quite precise, a single accelerating
mass can generate gravitational waves, a single test
mass at some distance will respond to those and there
is no _need_ for any other masses in between to
propagate the wave.

Is there a Universe that contains those two
masses-of-interest?

There is space, and IMHO "universe" is a term denoting
all of space and its contents of all forms.

So the interaction is couched in terms of "The Universe", and any
separation between "space" or "spacetime" and "contents" is purely
arbitrary... and cannot be experimentally disproven either way. So
"without the need" only applies to a single philosophy.

What are you talking about? Place a brick in a
vacuum, the brick is "contents" and the empty
bit around it is "space".

The vacuum around the brick doesn't have any
matter in it but it is still able to pass the
ripples we call gravitational waves and that
would still be the case if the brick were
removed.

Just because we do not include them in our analyses,
"the field" contributions from every bit of matter in the
Universe are still present.

The electric field is an attribute of space, it is
not generated by mass. It can have it's value altered
by charge which we usually associate with mass since
the only massless particles, photons, carry no charge.

Do you think that (charge :. mass) is mere coincidence?

...
http://lisa.nasa.gov/WHATIS/grav-wave.html

If LISA detects the waves then the model is as
well proven as you get in science, the ISM is
particles at a very low density so there is a
lot of empty space between them that those waves
must have crossed.

The volume is not empty. The volume only contains
little if any matter.

The waves would propagate equally well if it
contained no matter whatsoever.

The volume is still framed by a Universe, which has a
field that "supports" or "underlies" this volume.
Otherwise, we could not establish a size.

I see no connection between the existence of a field
and the ability to measure distance.

Distance = c * time

I can measure the length of my desk without
using time, just a ruler.

Redshift = Hubble constant * time
Intensity = 1 / (c * time)^2
... are you so sure of your lack of connection?

Yes.

...
... is devoid of mention of the matter/energy that
the curvature issued from. As if *your
interpretation* were the only one that survives. I
don't agree, and I apologize for bringing it up.

GR is a set of equations, "interpretation" doesn't
come into it IMHO. It should be possible to look at
the model of a BH and say where an external
influence at some time originated, near but outside
the horizon or inside. My point is that the result of
that is only valid within GR, and GR only gives one
answer.

It give two different answers, apparently.One in
terms of its "founding principles", and (at least)
one in terms of the formalisms adopted to
produce quantifiable predictions.

First I heard of that, what are these "two different
answers" and what was the question? AFAIK
only the equations make any predictions.

Two different answers:
1) matter does it,
2) curvature does it.

Does what? Matter causes curvature, curvature
causes .... gravity?

Your side of the discussion has concentrated on the mathematics, and
what the mathematics says. Before you said the "stress/energy tensor"
caused curvature. If A causes B, and B causes C, does A cause C? It
seems to me it must. It seems to me that it comes down to a
difference of opinion.

I think it is a difficulty of communication.

You feel that the field is separate from
matter/energy, and I don't. Since I am arguing from the position of a
Lorentz aetherist (in an entirely different argument), I will concede
that we cannot know. Will you also so concede (that the field may or
may not be separate from matter/energy)? I don't expect agreement...

The field exists everywhere in space since it is an
attribute of space. Think of it as a rubber ***
stretched taut. Place a small mass on the *** and
it bends and the amount can be modelled by maths.

What I am saying is that since the mass is localised
to one spot but the *** exists everywhere, the
existence of the *** does not require the mass. If
I remove the mass, the *** is still there, it is
just flat.

If two balls are placed some distance apart, they
will roll together because the curvature caused by
one extends to the other but that doesn't mean the
*** is made of balls and would not exists if they
were removed. The fact is that "***" exists in the
region between "balls" so can clearly exist on its own.

George


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