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Black Hole Information Loss Paradox Solution Proposed
Anuborn Satirak writes to tell us that Physicists from Case Western Reserve University claim to have cracked the black hole information loss paradox that has puzzled physicists for the past 40 years. "The physicists are quick to assure astronomers and astrophysicists that what is observed in gravity pulling masses together still holds true, but what is controversial about the new finding is that 'from an external viewer's point it takes an infinite amount of time to form an event horizon and that the clock for the objects falling into the black hole appears to slow down to zero,' said Krauss, director of Case's Center for Education and Research in Cosmology."
It's what happens in the physical world when you divide by zero.
This signature is a waste of 42 characters
Ah, esay one, I sloevd tihs one aegs ago, the irofntamion pbalbroy got lsot alnog the way.
Of course that's true, but is it also the case that a black hole can hold a stargate open, slowly sucking all of the surrounding area around the other gate into its time dilation bubble? Really, as a taxpayer funding this research, I want answers.
A slashdotter who didn't build his own computer is like a Jedi who didn't build his own lightsaber.
Here's the preprint.
I came here for a good argument
Are they saying black holes are perpetually in the creation phase, or they just don't exist at all unless they formed at the beginning of time?
from an external viewer's point it takes an infinite amount of time to form an event horizon
Nothing like an experiment to verify theories. And indeed, a quick trip to the DMV or the social security office confirms that it does seem to take an infinite amount of time for any event to occur, and that the clock seems to stop locally.
See? no need for black holes.
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
Anyone know what happened to Hawking's proposal for information loss?
o n_paradox
Basically what Hawking said (in a late essay entry in a science conference) was that Black Holes do 'digest' information and therefore you have information loss, however (and this is where his proposal was a bit controversial) Hawking suggested that the conglomeration of parallel universes will have a particular Black Hole present in one, and the same Black Hole missing in another, therefore the TOTAL information for ALL Universes, is retained.
Here's a link to Hawking's Black Hole Paradox: http://en.wikipedia.org/wiki/Black_hole_informati
And from the wiki article, here's the line I'm mentioning in my post:
"...On October 28, 2006, The Discovery Channel aired a show called "The Hawking Paradox". The show explained Hawking's conclusion that one must look at the universe as a whole, and that information lost in black holes is saved in parallel universes where no black holes exist."
It seems that this new solution is completely disregarding Hawking's proposal and replacing it with a new, stretched solution.
A black cat crossing your path signifies that the animal is going somewhere. -- Groucho Marx
A Slashdotter would realize that if you don't want to see any information, you need to view the event horizon with a threshold of -1.
would be proud.
Welcome to the Panopticon. Used to be a prison, now it's your home.
I'm sure it's not that simple, but that sure seems like what the article is saying. Black Holes would take infinitely long to form, so we'll never see one form, so no information will be lost. It sure doesn't seem to add up to me, since I thought there was pretty good evidence for black holes--and the universe hasn't existed for an infinitely long time. Still, when has quantum stuff ever made sense?
Then everything is complete and the Universe is in harmony. Problem solved.
Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
What truth?
There is no dupe
Firstly, they emphasize in their paper that they are considering their problem from the point of view of an external observer, rather than the point of view of an observer falling into the black hole. They write: They also contrast their results with previously accepted analysis of black hole formation: So, in essence, they are presenting findings that suggest that even quantum effects are taken into account, the collapse takes an infinite amount of time. This is signficant because it means that while the collapsing mass can appear to get closer and closer to being a singularity, it can never really achieve this final state to an external observer. How this relates to information loss is then described: So, in essence, the collapse of the black hole takes an infinite amount of time, during which time the black hole will evaporate via Hawking radiation. So objects falling into a black hole will never actually be swallowed up into the black hole (though they will get arbitrarily close and arbitrarily crushed!). Since the collapse is never really complete, information about the objects is never entirely lost. The emitted radiation will thus contain 'information' about the infalling objects. This in some way can be seen to resolve the seeming information paradox, whereby black holes were seemingly able to 'swallow up' information and completely destroy it (whereas no other process in the universe appeared able to do so).
There is an article about this same thing in new scientistb lack-holes-really-exist.html
http://space.newscientist.com/article/dn12089-do-
It quotes 't Hooft as claiming that "The process he describes can in no way produce enough radiation to make a black hole disappear as quickly as he is suggesting." So I am skeptical.
That is what I have always heard as well. I don't think that is the new part - probably just bad editorialism. It sounds like the new part is about the formation of the black hole itself - namely that to an outside observer, a star (or other large mass) will appear to take an infinite amount of time to collapse into a black hole and thus will appear to never form an event horizon.
So we finally have a possible answer to why we see so many dupes. ....
1. They aren't dupes and they don't exist because they never form
2. they are dupes but come from another universe where they have been deleted and saved here....
we haven't (seen any black holes). You can't "see" a black hole (that's why they're named as they are). We have observed the effects of things which match our expectation of the effects a black hole would cause. I assume the authors of this paper explain how their black-hole-like-object-which-isn't-a-black-hole can cause the same effects.
"National Security is the chief cause of national insecurity." - Celine's First Law
No, that's not correct. Normal GR predicts that (in the frame of someone away from the BH) the person falling into the black hole will take an infinite amount of time to reach the event horizon. In GR infinite time isn't the same thing as never! In the frame of the person falling into the BH (the proper time frame,) the faller crosses the event horizon in finite time and hits the center quite quickly (for non-huge black holes). The confusion and controversy lies in the concept of infinite time. Some take it to mean that black holes can't actually form (and must either be primordial or not exist). But infinite time might be a finite distance away due to weirdness with coordinates. An object falling through an event horizon might pass through infinite future and then travel back in time from the infinite future to the current. In the outside viewers frame, there might be two copies of the in-falling person, one inside and one outside. In this scenario, black holes can exist, and can contain the mass of stuff that falls into the hole...before it falls into the hole! Or it could all be bullshit and artifact of a broken theory of gravity.
To my understanding, the suggestion is that the collapsing matter will never create a true event horizon (a boundary from which nothing can ever escape). However this doesn't prevent the matter from collapsing to an arbitrarily high density and creating an increasingly large escape velocity. Think of a dense chunk of matter (but not infinitely dense). It will warp spacetime around it significantly, and it will bend the direction of light rays significantly. If a ray of light strays too close to the center of this quasi-singularity, it will get caught in a tight orbit. Now, the orbit won't be truly stable, and the light ray will, after some rotations around the gravity well, finally escape.
The denser the quasi-singularity is, the more rays will get trapped (temporarily) in these orbits, and the longer they will stay trapped. At a certain point, when light is being trapped for 10E80 year, the object could very sensibly be called a black hole. For all intents and purposes, infalling light does not escape. In principle, in a very long time the light may escape. Or, according to this new theory, the black hole may evaporate before actually forming (although this, too, will take a long time). But the massive curvature of spacetime will still lead to all the light-trapping and time-dilating effects normally predicted for black holes. This theory is merely suggesting that the containment is not absolute. Eventually, the stuff will escape. (Although for material objects, they will have been crushed and distorted beyond recognition. But at least in principle, the 'information' about them wasn't lost.)
Under the new theory, objects of near-infinite density still form, and still (in any practical sense) trap all incoming matter. However the question comes down to whether the singularity at the center is a true singularity with a true event horizon, or a perpetually-collapsing mass that has not quite yet reached the point of being a true black hole.
No. Black holes aren't lopsided
Because if the black hole was big enough to suck in the CERN campus with its gravity, the matter from which it was formed would have the same effect.
It's well-established that, if you only consider relativistic effects, a black hole will never form. What this paper does is demonstrate that if you take quantum effects into account, it's still true.
"They redundantly repeated themselves over and over again incessantly without end ad infinitum" -- ibid.
What about for the infalling observer?
He's entered the black hole, and information has been lost to him. I can get my head around thinking that information is relative, but now the laws of the universe hold for some people but not others?
OTOH, if I was falling into a black hole, entropy's the least of my worries.
There are 10 kinds of people in this world: those who understand binary, and nine other kinds of people.
This article is identical to what we covered... in 300 level Modern Physics in college in 1983.
I don't see how this is new or radical, except for the general population, who seem to think that for every "black hole" there is a corresponding "white hole", or that when you "fall into a black hole", you somehow end up somewhere else.
You should read Feynman's lecture series; he has one from the 50's that debunks the idea of a "graviton" or a particulate carrier for gravity because of the need for it to have mass.
-- Terry
Achilles vs. the Tortoise all over again?
``Tension, apprehension & dissension have begun!'' - Duffy Wyg&, in Alfred Bester's _The Demolished Man_
they haven't (proven that event horizons exist). I'll paraphrase my earlier response, maybe repetition will help you learn. We have observed objects which exhibit behavior consistent with what we would expect from observing an event horizon. I expect that the paper which is the subject of this discussion explains how their black-hole-like-object-without-an-event-horizon can also exhibit the observed behavior.
"National Security is the chief cause of national insecurity." - Celine's First Law
That's a rather zen question, actually. In some ways it amounts to asking "What's the difference between the matter that forms the black hole, and the matter that is falling into it?" Conventionally, the answer would be: all the matter inside the event horizon is part of the black hole, and everything outside the event horizon is falling into it (or, rather, is being gravitationally attracted towards it, and may or may not actually fall).
If this new bit of theory is correct, then the answer actually becomes harder, because the event horizon never forms, so you can't really say that some matter is inside vs. outside. Of course there is probably a sensible way to define a "pseudo-horizon" based upon a threshold where the probability of light escaping sharply drops towards 0.
I guess another way of thinking about it would be to say that this hypothetical matter that is "at the center of where the black hole is forming" would inevitably be included into the collapsing mass and would thus, itself, become part of the black hole.
It's true that EMR that enters the event horizon cannot escape. The evaporation process, called Hawking radiation, is a quantum effect that has no conventional analogue. Basically, in quantum mechanics (or rather quantum field theory), it is predicted that "virtual particles" randomly appear and disappear all the time. These virtual particles actually carry the force of things like the electric fields, magnetic fields, gravitational fields, etc. (they also avoid 'action at a distance' problems...). So in the vacuum, you will get random particle-antiparticle pairs appearing at random, and annihilating each other a moment later (these constant fluctuations are very important in modern theories, actually). If you imagine one of these random fluctuations occurring right beside an event horizon, you can imagine that one of the two particles gets sucked into the event horizon, but the other one escapes and sails off into the universe. The particle entering the black hole will actually reduce its mass (not increase it, as one would normally expect... though the proof of this requires digging into the math quite a bit), and the particle that escapes thereby carries away some of the mass of the black hole. Thus, over time, the blackhole is basically emitting radiation and slowly 'evaporating.'
Now, I know this idea of "virtual particles" randomly appearing and disappearing sounds totally bizarre. In fact it sounds like pseudo-science or an overcomlicated story that particle physicists are weaving. However these effects do have experimental backing (e.g. Casimir forces).
It turns out the rate of evaporation increases as you decrease in size. So really "micro black holes" (it is predicted that they will be created in upcoming particle accelerators) will evaporate very quickly. Big black holes will evaporate slowly at first, but then faster and faster as they shrink, until they get very small and release the last of their energy, in some sort of burst, yes. However a fundamental, unanswered, question is whether the radiation being emitted by the black hole contains 'information' about the states of things that went into the black hole. No one knows for sure. The conventional answer was that any information that goes into a black hole is lost forever.
However to many scientists, this answer was unsatisfactory.
Over a nice meal.
Reality is fluffy!
That's an interesting viewpoint, but I don't think you understand physics.
QM lies at the physical border of observable physics. At the QM boundary, concepts we take for granted such as electrons and the speed of light have different meaning. Humanity has nothing to do with it. At a small scale, the behavior of matter changes.
Here's an analogy:
Let's say Newtonian (ordinary) physics involves sitting on the side of the road and tracking how fast people are driving in their cars. From this perspective, you can get a pretty good idea where the cars are going. But there's still some randomness to it, if some driver changes their mind.
In this analogy, QM would be like sitting inside each car tracking who is having what conversation, who is on their cellphone, whether their hands are on the gearshift or on their girlfriend's boob, etc. It's a whole other level that you can't see from the side of the road.
If you could be inside each car, then you would know. But you can't. That's QM, the individual decision-making of each driver on the road.
Each driver==each electron. Whether you choose to track electrons with free will or with robotics, it's still too small and random to keep track of all the time.
Not to start a flamewar or anything, but I would like to "put forth a slice of personal philosophy". Over the years I have come to be quite skeptical when I hear/read expressions like "infinite amount of time" and "arbitrarily close" as they relate to the real world (or our interpretation of it) rather than a purely theoretical treatment. Take for instance Newton's Law of Cooling which implies that your Betty Crocker brownies will take an infinite amount of time to reach room temperature after removing them from the oven. Or that the magnitude of the electric field near a point charge "grows arbitrarily large" as you get "arbitrarily close" to it. As a mathematician, I love infinity, I really do --- there are infinitely many of them to choose from! But, IMHO, they don't belong in models of the physical universe (apart from simplifying calculations such as integrals over R^3). I don't believe that time is of infinite duration, that space is without bound, or that either one is infinitely subdivisible. Matter and energy are quantized, why not space and time? It has a nice symmetry to it --- a fan favorite for both mathematicians and physicists.
Your own assumptions about the universe is just a belief mind you.
You would like the universe to be like our models, of mathematics, that we created in order to understand and predict this universe. This mathematics is *within* the universe, so how this ever can be capable of holding all the parameters / the absolute truth, now *that* is irrational!
So the whole premise, although very tempting, is just impossible. The universe does not exist out of mathematics, mathematics exists because of this universe! To think any differently is perverse, and will only cloud your own judgement and mind. We must always be open to new stuff in order to advance true science, and not dogma.
Free-will or not, has nothing to do with it. The quantum-level is so low a level, that when we observe something, we irrevocably change the state. If we measure it a different way, we change the state in a different way. So wether we have free will or not, we can measure things differently, and the way we do it, will affect the result differently.
Wether we choose it by "free will", or by magic, or by rolling a dice, is just philosophy and has nothing to do with physics. You can always say this was predetermined, but the argument is that if we do it the other way, it will have different effects, that we *can* measure in experiments.
Said in a different way: Whatever we do, or dont do, we irrevocably are part of the dynamics of the universe. We would maybe like to be totally impartial observers, but when the observing itself changes the universe, how can we ever separate us from the rest of the entire universe? If you follow this logic, which yourself started, you will come to conclusions that borders on the religious, wether you like it or not. That were responsible for what we do, or dont do, even if its just observing.
So wether we have free-will or not, which is just a matter of frame of reference, where information comes from or not (we really do not know). But we have proof that we are irrevocably part of this universe and influencing everything in it, even just by observing.
So to have hope to understand such a changing system logically and reasonably, we first have to understand our self.
http://www.debunkingskeptics.com/
As they use the common technique of truncating the field degrees of freedom to a finite subset in the treatment of the Wheeler-de Witt equation,specifically, by only treating the radial R, they limit themselves to spherical domain walls instead of lenticular domain walls. A rotating mass in collapse tends lenticular (although that is a vast oversimplification), so the short answer is that they do not really treat the case of rotating masses.
Likewise, they are dealing only with domain walls of zero thickness.
However, this does adequately describe any given spherical domain wall of uniform density; nonspherical domain walls can be treated as a set of spherical domain walls with nonuniform density. However, I'm not sure if the tensor describing a nonuniformly dense domain wall is even solvable with current techniques or not; a lenticular tensor may be easier, but as this is at the very grey edge of my math skills, I haven't the foggiest idea if that is true for the general treatment of the Wheeler-de Witt equation.
Reading the preprint is rather informative; while the math is a little beyond my grasp, the concepts are not, and their 'conclusions' are very enlightening, as they detail problems in their analysis that suggest possible issues.
First, they deal with the lack of rigorous treatment of unspecific backreaction, and state that until such treament is available the final fate of the collapsing object is indeterminate.
Second, they deal with their assumptions and the possible changes in their results due to their assumptions (the zero thickness domain wall, the domain wall being spherical and of uniform density, their truncation of superspace to minisuperspace, the lack of allowance for possible third quantization due to annihilation and creation of domain walls, their Langrangian not breaking down near the Shwarzschild horizon, etc, all of which are in the preprint).
It is quite a fascinating read.
Indeed. That would solve the short-term mathematical problem, but not the deeper mismatch of the theories. Also, whether or not Hawking radiation is truly random, or whether it contains hidden information (in a non-trivially chaotic way, mind you) is the central question that people are trying to answer. It's an unsolved problem. Your suggestion would probably get the "right answer" for any real-life measurement we're going to make on black holes anytime soon. But the math may be hinting that there is an underlying physical principle we've been ignoring thus far. This is what has physicists excited: the possibility that this hint may lead to another revolution in our understanding of the universe.
I see where you're coming from. We can't know whether the universe is fundamentally 'supposed' to be time-symmetric or time-asymmetric. So maybe the universe is ruled by equations of the sort you describe. However the really troubling thing is this: all the fundamental equations of physics are time-symmetric. These are the equations that are used to predict and model the existence of black holes. So it's really weird that time-symmetric equations predict the emergence of a time-asymmetric phenomenon. (If you have equations that don't differentiate between left and right, it would be surely astonishing if, after some algebra, the equation had a preference for left or right. Where did the preference come from? You probably made a mistake in your algebra!) The idea of time-symmetry suddenly being broken is tantalizing. It suggests that either we have a hidden assumption in our current models, or that the universe is really able to generate time-asymmetry from time-symmetric forces. Either realization, if proven, would be an important contribution to physics. So I guess it again comes down to physicists not just being uncomfortable with the inelegance of the current formalism, but also hoping that the resolution of this paradox will provide new insights.
Since my background is in chemistry, I also tend to think of the problem in terms of entropy. In which case, to a large extent the emergence of time-asymmetry just amounts to the axiom "the universe started in a low-entropy state" after which statistical mechanics nicely predicts all the phenomena we readily observe. (The viewpoint you describe, where given enough time the universe will simply wander into a low-entropy state, is actually quite compelling.) But that actually makes the black holes all the more tantalizing. Because in statistical mechanics, as you noted, even when you go into high-entropy states, you are not really destroying information. All systems can, in principle, return to previous (even low-entropy) states. (In fact there are equations that allow you to approximate what the 'recurrence time' for a given system will be... where eventually it will return to its initial condition, even if it is a highly-ordered state.) However in a universe with black holes destroying information, this no longer holds true. If you follow the 'information' in such a un