feeding a black hole (APOD 27 Jun 2008)

[astrolabe]

Hello kovil and Henk21cm,

Seems logical that in order to escape from a BH than time must reverse.
Since IMHO light standing still, or othewise restricted to zero, translates to essentially infinity then the other side of that is time reversing. The idea I get, the process is much more difficult.

[Qev]

"Conservation of Information" is, I think, a consequence of quantum field theory, but I only have the most basic of layperson's understanding of anything quantum-mechanical.

From what I can tell from reading various sources, Hawking radiation is an offshoot of the Unruh effect, but the explanations are waaay out of my league. oO

[kovil]

It is good you take me to task on this. My great idea suddenly seems rather unwell thought out.

I was seeing Inertia (by which I mean Momentum also, and the rotating I spoke of was meant as angular momentum) as being the conglomerate angular momentum of everything inside of the event horizon.

What i didn't express was the idea of 'how does baryonic mass communicate amongst itself'. How do all the baryons in the Earth agree upon the aggregate angular momentum which the Earth has? I was avoiding this 'problem' of communication, and assuming that all the matter inside of the event horizon would use the same method of determination as the Earth does.

Yes, mass X velocity = inertia , of one sort or other, angular or linear. And this product = the information that the black hole, or rather whatever is inside of the event horizon ( I incorrectly use black hole and inside of the event horizon interchangeably at times) can tell about itself. In some way the angular momentum inside the event horizon, seems to me, is able to affect the material outside of the event horizon. Just as the gravity of the mass inside the event horizon can affect the matter/mass outside of the event horizon. (how does the gravity of the mass inside the event horizon affect the surrounding material outside of the event horizon, if nothing of a light speed nature can escape?)
Ah yes, the bending of the fabric of space-time, hmm, not so sure I accept that explanation, and this leads me away from mainstream explanations in many ways.

I was imagining that inertia would transmit some kind of information about what was inside the event horizon to the material in the local vicinity surrounding it. Unfortunately I had not gotten around to how it would do this, or what exactly it would say about itself. I guess I was hoping this idea would spark some kind of answer in your mind.

This is why I am an amateur, I don't spend enough time or energy on my own ideas!

[henk21cm]

G'day Kovil,

I was seeing Inertia (by which I mean Momentum also, and the rotating I spoke of was meant as angular momentum) as being the conglomerate angular momentum of everything inside of the event horizon.

Ahh, now i see. The sum of all rotations of particles leads to some sort of axis, which is the main axis of rotation of the black hole and thus the inertia you proposed.

How do all the baryons in the Earth agree upon the aggregate angular momentum which the Earth has? I was avoiding this 'problem' of communication, and assuming that all the matter inside of the event horizon would use the same method of determination as the Earth does.

Mainly friction between particles. Rocks can be either crystaline (granites) or amorphous (caustic rock, cooled lava's). Electric bonds keep the particles together. Pebbles on the beach stay together as well, predominantly by friction. Heaps of pebbles are dangerous, so don't fool with them, you will get burried alive. Nevertheless you can study friction between pebbles by making a small heap (0.5 m high) of pebbles. If you make the slope too steep, more than about 35°, pebbles will slide down. The reason: the amount of friction is too small to hold a pebble in equilibrium with gravity working on it. This is called Coulomb friction.

In some way the angular momentum inside the event horizon, seems to me, is able to affect the material outside of the event horizon. Just as the gravity of the mass inside the event horizon can affect the matter/mass outside of the event horizon.

What's inside the event horizon can influence what's outside, mainly by gravitational forces. So the only information that seeps towards the outside of the event horizon is the amount of mass. Whether it is dark mass, the number of particles that make up the mass, that is all hidden. The only way the inside of the event horizon can influence the outside world is pulling it inside. The gradient of the gravity, which can be measured in the outside world by the degree of deformation of a region filled with galaxies (see e.g. the Abell cluster 2218) provides you information about the sheer size of the event horizon and thus its mass.

Ah yes, the bending of the fabric of space-time, hmm, not so sure I accept that explanation, and this leads me away from mainstream explanations in many ways.

If i read this correctly, you are not in favour of the General relativity theory. Correct me if i'm wrong. General relativity has indicated that mass curves or bends space. Experimental confirmation of this theory was given in 1919. Precession of the perihelion and accurate time measurements on earth have all confirmed Einsteins master brain child.

I was imagining that inertia would transmit some kind of information about what was inside the event horizon to the material in the local vicinity surrounding it.

I do not know whether this analogon is correct. If you position a rotating cylinder in a tank of water, the water around this cylinder is dragged with it. It starts to rotate. This is mainly due to the shear forces between the solid edge of the cylinder and the water. The 'no slip' condition says that the water velocity precisely at the wall of the cylinder is zero with respect to the wall. Such a 'no slip' condition does not hold IMHO on the event horizon. Rotation of matter outside the event horizon is mainly caused by the conservation of angular momentum. The closer it gets to the event horizon, the smaller the radius is and thus the faster it has to rotate. Nevertheless it is not farfetched to come up with a situation in which the accretion disk rotates opposite to the rotation of the black hole.

Qev wrote about quantum information and the conservation of information. Conservation of energy is well known. Due to the many experiments which do not reject energy conservation, it became the main pilar of physics. If conservation of energy would after all not be valid, my view on the cosmos would collaps. Conservation of information has not reached that status. The form of information spread by quantum field theory i can think of is the double slit experiment. If the spin of one beam (wave function) inside the event horizon is determined, the spin of the other part of the wave function outside the event horizon is known. That is a way in which information would seep out of the inner world of the event horizon. Maybe that is meant with "conservation of information"?

Astrolabe wrote about reversing time to escape from a black hole. Basically that seems logical, since when time reverses, like a film reel spinning the movie backwards, the infalling material becomes outgoing material. How to reverse time, he nor i do know. What General relativity predicts that an observer far outside the region of influence of the black hole notices that a particle approaching the black hole its (particle) time progressively gets slower. When the particle is at the event horizon, time has come to a halt. What hapens inside the event horizon, well, 20 years ago i read something about that, can't remember it exactly and now i'm trying (already a few weeks) to find the chapter in one of my books. Did not succeed yet.

[kovil]

Try the last chapter in Hawking's 'A Brief History of Time'.
If my memory serves me well.

We each have our way of seeing, or imaging, the world; and so there is a large conceptual gulf between us of translation losses. That can get worked thru over time.

I have a lot of homework to do to get up to speed in talking about all of this, as I've been onto other subjects for a while, and my logic seems to be rather swiss cheese lately.

[Qev]

What hapens inside the event horizon, well, 20 years ago i read something about that, can't remember it exactly and now i'm trying (already a few weeks) to find the chapter in one of my books. Did not succeed yet.

The GR explanation I always encounter, or at least an approximation of an explanation , is that beyond the event horizon, one of the space dimensions gets swapped with the time dimension, such that the singularity is no longer "at the center" so much as it is in the unfortunate traveler's future; ie. the traveler cannot avoid the singularity, any more than they could avoid traveling forward in time when they were outside the event horizon.

'Conservation of Information' seems to be a generally-assumed aspect of physics, but be darned if I can find a formal statement of it (that I can grasp ) anywhere.

[starnut]

Still on topic but going off slightly on a tangent...

Does dark matter get sucked into the black hole just like normal matter? After all, there is more dark matter in the universe than normal matter. If so, it would be interesting to know what happens at the singularity where dark matter would be forced to merge with normal matter.

Gary

[henk21cm]

G'day folks,

"Conservation of Information" is, I think, a consequence of quantum field theory, but I only have the most basic of layperson's understanding of anything quantum-mechanical.

In the meanwhile i learned that there are two laws of conservation of information. One is adopted by religious groups and organisations which prefer creation above evolution. The other is in the realm of quantum mechanics (QM). The latter is the focus of this discussion.

A nice Gedankenexperiment is described by Amanda Gefter: what happens when an elephant crosses the event horizon. Below her article a short essay deals with pair formation (particle-antiparticle) near the event horizon, as described earlier in this discussion. Another new idea recently popped up: the space time fabric is a real fabric, it has threads (yarns), it is not a continuous medium. http://www.physorg.com/news130000012.html

Try the last chapter in Hawking's 'A Brief History of Time'.
If my memory serves me well.

Tnx for the suggestion. That book is unfortunatedly not in my collection. When the autumnal weather conditions we currently endure will settle a little (not for the comming 15 days according predictions), i can jump on my bike and go the the city in a quest to obtain that book. It is not that expensive, about 15 Euros.

Does dark matter get sucked into the black hole just like normal matter?

AFAIK dark matter is matter that does not show itself in the electro magnetic spectrum, is reveals its presence by changing orbits of non-dark matter, due to its gravitational pull. Since gravity is a rather serious issue in combination with black holes, i am very sure -by simularity- that dark matter is to be effected by black holes as well. I see no fundamental reason why dark matter would not be attracted to black holes. Outside the event horizon dark and non-dark matter live together in perfect harmony, of a kind, a maried couple would dream of. There is no violent reaction when both meet.
Gary, why do you think they would react differently inside and outside the event horizon?

[Qev]

Something that's bothered me recently about the black hole information paradox: why is it a paradox at all? Due to relativity, from the point of view of a distant observer nothing ever actually falls into a black hole in the first place, but rather objects approach asymptotically close to the event horizon as their image becomes more and more redshifted. Or is there something I'm missing, here?

[henk21cm]

Something that's bothered me recently about the black hole information paradox: why is it a paradox at all? Due to relativity, from the point of view of a distant observer nothing ever actually falls into a black hole in the first place, but rather objects approach asymptotically close to the event horizon as their image becomes more and more redshifted. Or is there something I'm missing, here? :)

No, your description is correct.

<<Quote: {space.newscientist.com, Amanda Gefters story}
Which brings us back to the elephant. Let's say Alice is watching a black hole from a safe distance, and she sees an elephant foolishly headed straight into gravity's grip. As she continues to watch, she will see it get closer and closer to the event horizon, slowing down because of the time-stretching effects of gravity in general relativity. :: What Qev called red shift:: However, she will never see it cross the horizon. Instead she sees it stop just short, where sadly Dumbo is thermalised by Hawking radiation and reduced to a pile of ashes streaming back out. From Alice's point of view, the elephant's information is contained in those ashes.
Inside or out?

There is a twist to the story. Little did Alice realise that her friend Bob was riding on the elephant's back as it plunged toward the black hole. When Bob crosses the event horizon, though, he doesn't even notice, thanks to relativity. The horizon is not a brick wall in space. It is simply the point beyond which an observer outside the black hole can't see light escaping. To Bob, who is in free fall, it looks like any other place in the universe; even the pull of gravity won't be noticeable for perhaps millions of years. Eventually as he nears the singularity, where the curvature of space-time runs amok, gravity will overpower Bob, and he and his elephant will be torn apart. Until then, he too sees information conserved. :etouQ>>

There is no paradox! Or is it?

[Qev]

Ahhhh, I guess that clears up things then. The last step would probably (to the external observer) take an inordinately long time, though. I guess this rules out black holes being possible pathways to antigravity universes, since it really -would- lead to information loss.

[astrolabe]

Hello All,

Typed in a post yesterday but It appeared that the page timed out 'cause when I chose "submit" my post disappeared. I guess I took to long. My only barrier to the forum is the keyboard. Or rather my feeble use of it.

I was trying to retract a previous post I composed regarding time reversal being a possible explanation for hor Hawking radiation could occur when nothing, not even light, can escape through the event horizon of a black hole.

[iampete]

. . . As she continues to watch, she will see it get closer and closer to the event horizon, slowing down because of the time-stretching effects of gravity in general relativity. :: What Qev called red shift:: However, she will never see it cross the horizon. Instead she sees it stop just short, where sadly Dumbo is thermalised by Hawking radiation and reduced to a pile of ashes streaming back out . . .

OK, now I'm lost (or, to put it more correctly, even more lost than before).

In essence, what that says, is that nothing disappears "into" a black hole. What that description seems to imply is that there is no possibility for mass accretion of a black hole once it's formed.

The "Bob riding the elephant" scenario, flatly contradicts that.

What am I missing here?

[astrolabe]

Hi All,

Me again. The fact is I had retyped my post a second time yesterday thinking I somehow goofed and messed up the first attempt. Well, sorry to say, my second try also took too long and when I hit "submit"...... you guessed it! It disappeared as well. So this time I'm piecing it out.

In the 1970's I think, Steven Hawking embraced time reversal as a logical idea in a collapsing-universe theory but only for s short time. Now I've seen several occasions where time reversal and antitime have been used interchangeably but, for the record, I think they describe two separate ideas and IMO it is not correct to mix the two up. Time is my favorite subject and I sense that these are two unrelated lines of thought.

[apodman]

I'm not betting the baby food money on the idea of conservation of information. It sounds to me like an idea without much proof.

Supposedly, quantum information can't be destroyed. Okay, I have a proton and a neutron. They each have 1/2 spin. I would say that "here is a neutron with a spin of 1/2" and "here is a proton with a spin of 1/2" are two pieces of quantum information. I send the proton and neutron off to an extreme place where they are busted into their constituent quarks: 2 up quarks and 1 down quark for the proton, 1 up and 2 down for the neutron. I look at my 3 identical up quarks and 3 identical down quarks, and I can't tell which came from the proton and which from the neutron. So where have my original two pieces of indestructable quantum information gone?

I'm not trying to be a wise guy here. I'll grant you I haven't studied enough to form the correct concept and question, but what am I missing?

[apodman]

when I hit "submit" ... It disappeared

A common problem. If I've taken a long time to type, check my facts, tend to dinner, or whatever, I select all the text I'm about to submit and copy it to the clipboard before my submission attempt fails. That way my second submission attempt is a quick paste-and-submit with no retyping.

I won't say how many times I got burned before I started remembering to do this. 8)

[astrolabe]

Ahem,

Now where was I..............Oh yes. A person at a safe distance from a black holes's event horizon will see a particle's a time slow down as it nears the EH to the point that at the EH it's time will stop. what happens on the other side of the horizon is unknown but, could it be be known if the particl/antiparticle relationship was determined? If one knew what a particle is doing (or should be doing) would it necessarily lend insight to what an antiparticle is or should be doing? Kind of like using a magnet under a sheet of paper to drag iron filings around. What is that theory about two particles in different locations mirroring each other. Something like that perhaps. Probably doesn't apply to oppositely charged units anyway.

[astrolabe]

OKAY, this is it:

Time reversal as an escape mechanism I can see now probably wouldn't work because as soon as the radiation escaped through the Event horizon of a black hole then time switches back to normal and it would seem that an occillating effect then is created. So nope that isn't it.

Hmmmmmm. Well then that only leaves the obvious- gravity. it seem to be the only logical force/wave that permeates the event horizon in either direction (directionless?) without questioning any laws or creating any serious breakdowns of physics. The question does arise, however, that if a graviton is the CARRIER of gravity could radiation in some form hitch a ride on a graviton or ride a gravity wave if outside matter is present?

There! That, after much consideration, the point of all this. But I thought the presentation of how I arrived at would help form the idea better.

Thank you for your patience. Dan Drayer

[astrolabe]

Hello apodman,

Can't thank you enough. I'll certainly give it a whirl.

[apodman]

What is that theory about two particles in different locations mirroring each other.

I think it's "strange action at a distance".

Or "spooky action at a distance". - Einstein

Or "quantum entanglement".

http://en.wikipedia.org/wiki/Quantum_entanglement

http://en.wikipedia.org/wiki/Quantum_information

[Qev]

Hmmmmmm. Well then that only leaves the obvious- gravity. it seem to be the only logical force/wave that permeates the event horizon in either direction (directionless?) without questioning any laws or creating any serious breakdowns of physics.

Actually, any of the forces would be able to 'permeate the event horizon', assuming the black hole carried a charge of that particular force. An electrically-charged black hole is a possibility, albeit a short-lived one (as net electric charges tend to neutralize relatively quickly in nature).

[kovil]

< The question does arise, that if a graviton is the CARRIER of gravity, could radiation in some form hitch a ride on a graviton or ride a gravity wave if outside matter is present? > - and carry inside event horizon information to outside the event horizon.

In my view of all this, Energy and Inertia combine to make protons and neutrons (electrons don't have Inertia as a prime ingredient, they are like the radiative electro magnetic spectrum energy in this respect. A light beam or a radio wave energy doesn't have 'inertia'. The reason electrons exhibit relativistic slowing on approach to light speed in particle accelerators is due to their 'energy density property' -which light beams and radio waves do not have).
(an electron is a negative electric charge squeezed down to the size of an electron from the size of its awareable universe! A proton is a positive electric charge squeezed down to the size of a proton from the size of its awareable universe! )

Inertia is how 'gravity' can get its hooks into matter and 'pull' on it. Only things with this 'Inertial' component to begin with are affected by gravity. Electrons are not affected by gravity, they are affected by electrical effects, or Energy in its myriad of forms.

I expect that none of you think this way so my arguments will be double difficult to follow or accept, c'est la vie.

At the event horizon Inertia containing particles are being pulled so fast that any electromagnetic events emanating from them are not able to move away. Perhaps this seems at odds with GR, but 'the speed of light' is not a speed, it is the 'Ratio of Space to Time'. There isn't a way to go 'faster' than the ratio of space to time, as the way the universe is structured it has no way to do this.

I'm getting afield of the intention here. The idea was that Inertia is a primary component in matter, and gravity pulls on matter that contains Inertia, and matter is actually only Energy in the final result. Somehow Inertia is combined with Energy to form protons and neutrons, but not with electrons. Electrons are purely an electrical phenomena, or Energy. This incompatibility between protons and electrons keeps the hydrogen atom from electrically neutralizing, but still charge attracted.

I was seeing a black hole as an Energy sink, where Energy can't get out, but Inertia can still transfer some information past gravity's pull. Exactly how, I haven't understood yet.

This was in the next steps leading to; a braking mechanism on black hole growth, to restrict rapid unlimited growth of black holes in complete disregard of their surroundings. This braking mechanism might actually prevent black holes from forming at all.

And remember, "As nature abhors a vacuum, it likewise abhors a black hole" !!

[bystander]

I haven't been able to find much on "Conservation of Information" (except for Dembski and ID, and I don't want to go there). I did find an article by Scott Hitchcock (http://arxiv.org/PS_cache/gr-qc/pdf/0108/0108010v2.pdf) that talks about BH's as logic gates and the universe as a quantum computer.

What about "quantum entanglement"? If a particle is "lost" to a BH, could its "entangled" particle conserve the information of the lost particle? Would another particle then become entangled?

And what about Alice and Bob and their elephant? Is there another "entangled" elephant (and Alice and Bob, or maybe Carol and Ted). And what about the turtle the elephants are standing on?

[Qev]

Actually, I think the situation you've just described was the foundation of the 'black hole information paradox', if I'm reading the wiki article right.

[bystander]

Parallel universes? Very interesting. See The Hawking Paradox http://uk.youtube.com/user/BastardScience