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| e goldstein |
 Posted: Thu Feb 10, 2005 1:11 am |
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According to theory, a black hole can still support it's outer
gravitational field, even though its escape velocity is faster than
light (and light-speed gravitons), on relic gravitation.
According to General Relativity, from an outside reference frame, a
black hole takes forever to form. So there will never be a time when
light-speed gravitons, forming the gravitational field, get trapped
inside the black hole.
But from the perspective of the black hole forming, or someone falling
into a black hole, everything takes place in a short amount of time,
and the outside universe rushes through an infinite amount of time in
a heartbeat.
So if virtual particles were to be split up by one of the pair falling
into the black hole and the other radiating away the mass of the black
hole, wouldn't that have to happen an infinite time in future after
the black hole forms? |
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| Fat Cat |
| Posted: Thu Feb 10, 2005 2:20 am |
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Black hole is black and you can't see it.
When it evaporates, you can't see either, thus it is safe to say that black
hole
went there and evaporated, since you have no proof that it hadn't.
"e goldstein" <me@1984.com> wrote in message
news:toul01t0a0td0ersgns3mggilimrug8trc@4ax.com...
[quote:ee03443579]According to theory, a black hole can still support it's outer
gravitational field, even though its escape velocity is faster than
light (and light-speed gravitons), on relic gravitation.
According to General Relativity, from an outside reference frame, a
black hole takes forever to form. So there will never be a time when
light-speed gravitons, forming the gravitational field, get trapped
inside the black hole.
But from the perspective of the black hole forming, or someone falling
into a black hole, everything takes place in a short amount of time,
and the outside universe rushes through an infinite amount of time in
a heartbeat.
So if virtual particles were to be split up by one of the pair falling
into the black hole and the other radiating away the mass of the black
hole, wouldn't that have to happen an infinite time in future after
the black hole forms?
[/quote:ee03443579] |
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| Nick |
| Posted: Thu Feb 10, 2005 2:21 am |
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e goldstein wrote:
[quote:554f481ced]According to theory, a black hole can still support it's outer
gravitational field, even though its escape velocity is faster than
light (and light-speed gravitons), on relic gravitation.
According to General Relativity, from an outside reference frame, a
black hole takes forever to form. So there will never be a time when
light-speed gravitons, forming the gravitational field, get trapped
inside the black hole.
But from the perspective of the black hole forming, or someone
falling
into a black hole, everything takes place in a short amount of time,
[/quote:554f481ced]
Wrong. How can proper time go any faster than gravitational
time?
Try to show me and I'll show you a chicken with teeth.
It can't. Time for objects in gravity can only go slower than
the - curved - time of gravity not faster.
There is only one time which can have two dilations - one
by accelerating and the other by gravity.
It must be known that both dilations can never end time.
Thank you for your time.
Mitch Raemsch -- Light Falls -- |
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| G=EMC^2 Glazier |
| Posted: Thu Feb 10, 2005 8:53 am |
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I think Hawking screwed things up saying "Black holes evaporate."
Gravity can split particle pairs,and still one falls into the BH. I
don't see that as evaporation. OK the other one gets a kick into
space.Getting that kick(energy) has a big mystery(problem) in my mind. I
begs the question. Why one and not both? Bert |
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| Sam Wormley |
| Posted: Thu Feb 10, 2005 9:20 am |
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Dr. Photon wrote:
[quote:d9e85fece0]Given that in GR they can form, and Hawking radiation exists, I still
have a question on how Hawking radiation behaves.
Given that a particle pair is created near to the EH, one falls in and
reduces the mass of the BH (which in itself seems a little odd, do you
have a handy reference?), the other tries to escape. But as it is near
the EH, the EH is "following" it, so the particle doesn't make much
headway. In most cases there is much more mass falling in a BH than
being emitted - even for a "starved" BH there is background radiation
falling in, plus presumably a fair amount of dust.
The point being that the mass is still usually increasing, so the EH
expands faster than light and swallows the particle it just "emitted".
I know Hawking radiation is predicted to be tiny for most BHs we are
likely to find, but according to the above effect even moderately
"starved" BHs would emit much less Hawking radiation than predicted,
or is this somehow taken into account? I can imagine the effect to be
negligible due to the large masses involved to change a BH diameter,
but I would appreciate a second opinion!
[/quote:d9e85fece0]
See: http://scienceworld.wolfram.com/biography/Hawking.html
Equation applies |
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| Uncle Al |
| Posted: Thu Feb 10, 2005 11:21 am |
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e goldstein wrote:
[quote:c1fe54d791]
According to theory, a black hole can still support it's outer
gravitational field, even though its escape velocity is faster than
light (and light-speed gravitons), on relic gravitation.
[/quote:c1fe54d791]
Already Dead on Arrival.
[quote:c1fe54d791]According to General Relativity, from an outside reference frame, a
black hole takes forever to form.
[/quote:c1fe54d791]
Doncha kinda suspect empirical observation has some conterveiling
bearing here?
[quote:c1fe54d791]So there will never be a time when
light-speed gravitons, forming the gravitational field, get trapped
inside the black hole.
[snip crap][/quote:c1fe54d791]
No gravitons.
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz.pdf |
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| Eric Gisse |
| Posted: Thu Feb 10, 2005 1:58 pm |
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Uncle Al wrote:
[quote:2484eff539]e goldstein wrote:
According to theory, a black hole can still support it's outer
gravitational field, even though its escape velocity is faster than
light (and light-speed gravitons), on relic gravitation.
Already Dead on Arrival.
According to General Relativity, from an outside reference frame, a
black hole takes forever to form.
Doncha kinda suspect empirical observation has some conterveiling
bearing here?
[/quote:2484eff539]
I point to Sgr A*...
:D
[quote:2484eff539]
So there will never be a time when
light-speed gravitons, forming the gravitational field, get trapped
inside the black hole.
[snip crap]
No gravitons.
[/quote:2484eff539]
So...no gravitation from a field theory? I see you comment endlessly
upon metric/affine theories of gravity as if they are the only choices
we have. Is there nothing else viable, like say, a field theory of
gravity? Or have all the known ones been rendered unviable through
experiment? Once upon a time you had a decent list of viable and
unviable theories of gravitation.
BTW, how goes the Eotvos experiment? I want to see GR broken.
[quote:2484eff539]
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz.pdf[/quote:2484eff539] |
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| tj Frazir |
| Posted: Thu Feb 10, 2005 2:21 pm |
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It just changes directions.
its orbital paths are smashed to a fine line not going slower or faster.
when it gains the mass it cant conevrt it to speed and cant orbit
lower.
Wile more mass is crushed into the fine line of orbit.
enouph mass will make it speed up.
But it cant speed up so it changes directions. |
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| Nick |
| Posted: Thu Feb 10, 2005 7:06 pm |
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So through the entire orbit loop the mass doesn't change.
I see that. |
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| tj Frazir |
| Posted: Thu Feb 10, 2005 11:32 pm |
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the orbit loop around the center of the atom it changes mass all the way
around in the energy slope of gravity. |
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| Nick |
| Posted: Fri Feb 11, 2005 12:46 am |
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I'm refering to planetary orbits.
Is it all the same?
If orbit is all freefall the mass should be maintained.
I admit this is what Einstein said about falling
mass; its converted into motion but
it remains constant because that
motion gives it back the same amount of mass.
Falling gives matter the same amount of mass as is lost
in the fall into a slower time. That is what Einstein said.
In your language he might have said gravity is a push
to a slower time. Slower time is what deminshes mass
for him.
Light in gravity is the same way. Its energy is conserved.
Light starts off redshifted where it is emmited.
And maintains that energy - falling in gravity. |
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| Dr. Photon |
| Posted: Fri Feb 11, 2005 7:11 am |
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Sam Wormley <swormley1@mchsi.com> wrote in message news:<Y4KOd.62617$eT5.32976@attbi_s51>...
[quote:dd1012adca]Dr. Photon wrote:
[snip]
I know Hawking radiation is predicted to be tiny for most BHs we are
likely to find, but according to the above effect even moderately
"starved" BHs would emit much less Hawking radiation than predicted,
or is this somehow taken into account? I can imagine the effect to be
negligible due to the large masses involved to change a BH diameter,
but I would appreciate a second opinion!
See: http://scienceworld.wolfram.com/biography/Hawking.html
Equation applies
[/quote:dd1012adca]
Thanks for that, the problem I have relates to the assumptions that go
into the radiation calculation. From a general thermodynamic argument,
it seems that it is not entirely valid for a BH which is gaining mass
and thus recaptures the emission it just emitted, i.e. it hasn't
really emitted at all in that case.
The more I think of it, the less significant I think this recapturing
will be. But it looks possible, at least.
Going back to the original post:
"Black Holes and Particle Emission"
http://dnausers.d-n-a.net/dnetGOjg/Black/Holes.htm
"As energy cannot be created out of nothing one is positive and one is
negative. ... In the presence of a black hole a particle with negative
energy can fall into the hole no longer annihilating its partner. Its
partner now free may also fall into the black hole or escape carrying
away the energy (mass) given to it by the holes tidal gravity"
I have read similar descriptions before, and I admit to having some
trouble with negative energy particles. In the Coulomb field, the
virtual particles are positive energy, and real anti-particles also
have positive energy. But in the BH case, it seems to involve a real
negative energy particle. I can visualise negative energy referring to
a region of space where the expectation value of the E-field is less
than the average for free space - is a real negative energy particle
somehow a quantised version of this?
His description
"Where vacuum fluctions give rise to an instantaneously high value,
energy being momentarily stolen from adjacent space and then returned,
virtual particles and virtual antiparticles, are formed."
also doesn't seem to help much.
regards,
BR
p.s. I was very interested to find the following
http://arxiv.org/PS_cache/gr-qc/pdf/9704/9704038.pdf
about BHs that can pulsate, passable singularities, QM in black holes,
and the like. Some great references too. |
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| tj Frazir |
| Posted: Sat Feb 12, 2005 8:35 pm |
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by changing directions.
nothing is going to speed up or fall to center.
enouph change will only cause it to change directions and eject the
orbit. |
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| e goldstein |
| Posted: Sun Feb 13, 2005 4:20 am |
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On Thu, 10 Feb 2005 08:21:28 -0800, Uncle Al <UncleAl0@hate.spam.net>
wrote:
[quote:f59379c3c7]e goldstein wrote:
According to theory, a black hole can still support it's outer
gravitational field, even though its escape velocity is faster than
light (and light-speed gravitons), on relic gravitation.
Already Dead on Arrival.
[/quote:f59379c3c7]
Yeah and the moon landing never happened either...
[quote:f59379c3c7]According to General Relativity, from an outside reference frame, a
black hole takes forever to form.
Doncha kinda suspect empirical observation has some conterveiling
bearing here?
[/quote:f59379c3c7]
And what exactly is that according to your opinion? Einstein's theory
of GR has been proven on emperical observation.
[quote:f59379c3c7]So there will never be a time when
light-speed gravitons, forming the gravitational field, get trapped
inside the black hole.
[snip crap]
No gravitons.
[/quote:f59379c3c7]
No gravitons? GR is based on gravitation affecting things at light
speed. |
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| Jason |
| Posted: Sun Feb 13, 2005 10:37 am |
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Couldn't a bigger black hole destroy it?
Or i suppose after time and there is nothing for the black hole to
absorb, then wouldnt over a long period of time, it would generally
just break down, or is that impossible?
e goldstein wrote:
[quote:77d1d79f1a]According to theory, a black hole can still support it's outer
gravitational field, even though its escape velocity is faster than
light (and light-speed gravitons), on relic gravitation.
According to General Relativity, from an outside reference frame, a
black hole takes forever to form. So there will never be a time when
light-speed gravitons, forming the gravitational field, get trapped
inside the black hole.
But from the perspective of the black hole forming, or someone falling
into a black hole, everything takes place in a short amount of time,
and the outside universe rushes through an infinite amount of time in
a heartbeat.
So if virtual particles were to be split up by one of the pair falling
into the black hole and the other radiating away the mass of the black
hole, wouldn't that have to happen an infinite time in future after
the black hole forms?[/quote:77d1d79f1a] |
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