Famous Hawking Black Hole Bet Resolved?

Mick Ohrberg writes "In 1997 the three cosmologists Stephen Hawking, Kip Thorne and John Preskill made a famous bet as to whether information that enters a black hole ceases to exist -- that is, whether the interior of a black hole is changed at all by the characteristics of particles that enter it. It now looks like Stephen Hawking and Kip Thorne may owe John Preskill a set of encyclopedias of his choice, since physicists at Ohio State University 'have derived an extensive set of equations that strongly suggest that the information continues to exist -- bound up in a giant tangle of strings that fills a black hole from its core to its surface.'"

Comments

Hawking radiation

[Space cowboy]

Steven had posited in the 70's that the black holes leak (Hawking radiation), but the paradox is that they radiate a 'black-body' spectrum (entirely thermal radiation) in inverse proportion to their mass (so as they get smaller, the radiation increases). The problem here is that all the information went in, but it's very difficult to infer information from a black-body radiated spectrum (!). Steven therefore thinks that information is lost forever.

The article though is a bit hand-wavy over why the information is preserved in this new theory... (I guess Nth dimensional maths doesn't appeal to the reporter :-). I don't think the fact that the string-theory radius matches the black-hole radius is sufficient to prove the case, though it's an interesting pointer, a curious coincidence if indeed it is such ...

Effectively this is a conjecture - if the strings continue to exist, then they'd have the same size as the black hole appears to have. The throwaway statement " That means a black hole can be traced back to its original conditions, and information survives." seems a bit of a stretch though :-)

Simon

Re:Hawking radiation

[Gil-galad55]

In my physics experience, coincidence typically means you got the right answer... unless it's a test question, in which case you're probably wrong.

Re:Hawking radiation

[dandelion_wine]

No, NO, Space_Cowboy, you have got it ALL WRONG.

Now I want you to repeat after me:

- First
- Post
- !

Re:Hawking radiation

[kfg]

My experience is that that sort of coincidence is suggestive, in other words you've gotten something right, but determining just what that something is is often a)problematic, and b)not always what you thought it was at first.

KFG

Re:Hawking radiation

[Gil-galad55]

And then there are the times when you get lucky and get the right answer for the wrong reason... which is, I suppose, why we have peer review!

Re:Hawking radiation

[SeanTobin]

The thing about black holes emiting radiation is that they don't actually emit any radiation. Anything that enters the event horizon is gone - for good. It doesn't come back ever, even as black body radiation.

The way theorists get around this is through virtual particles. Assume that virtual particle pairs are blinking in and out of existance all the time, but are never noticed because before they become 'real' particles they destroy each other (think particle/anti particle). The fun part comes when the particles appear on opposite sides of an event horizon. One gets sucked into the black hole, and the other becomes a full-fledged particle with a small chance of escapeing. Because the escapeing particle was never in the event horizon to begin with, it can contain no information from within the black hole.

Now, how the black hole doesn't gain mass from the anti-particle I'm not quite sure... I'll leave that up to all the ./ theoretical physisists.

Re:Hawking radiation

[dnoyeb]

In my mathematical experience, coincidence usually means you have used circular logic/calculations somewhere. In effect proving your foundation.

But its always nice to figure out how you fooled yourself :)

Re:Hawking radiation

[kfg]

Damn that peer review. The Nobel board laughed at me when my theory was submited, but I'll show them. Yes, I'll show them.

Mwuhhahahahahahha!

KFG

Re:Hawking radiation

[smittyoneeach]

Because you are right, your loose definition of tautology is true.

Re:Hawking radiation

[Anonymous Coward]

I suppose, why we have peer review!

Peer review might help, but normally people attempt to recreate the experiment. That's how science weeds out "luck".

Re:Hawking radiation

[CAlworth1]

IANATP (theoretical physicist), but I think I may be able to shed a bit of light on the last question.

As I understand it, the idea is that the particle and the anti-particle come into being at the same place, moving in different dirrectsion, and the anti-particle is more prone to being pulled in somehow due it its being the opposite of the other mass in the black hole. The particle escapes, generating the black-body radiation, and the anti-particle enters the black whole and collides with a corresponding particle, leaving existance as the original particles came into existance - messed up I know.

If anyone is curious, (stolen from The Universe in a Nutshell by Stephen Hawking, the temp of a black hole is

Temp = (h * c^3)/(8 * pi * k * G * M)

where h is planck's constant, c is the speed of light, G is Newton's gravitational constant, k is Boltzman's costant,T is temp, and M is the mass of the black hole.

Re:Hawking radiation

[imsabbel]

Well, you are mostly right.
BUT:
If an anti-particle enters the black hole, it LOSES mass. So its a process in which energy is emitted outside of the event horizon and the mass inside the event horizon is decreased. That no mass actually transfered out of the black hole is only a semantic problem (like tunneling, ect).

I cant really speak about the asymetry that enables this process, because its a few years about my quantum physics level, but it could be possible.

Btw: There are theories that the resulting radiation isnt REALLY blackbody radiation, but only "shaped" like BR, but with an "overlayed" information contend.

Re:Hawking radiation

[nihilogos]

The article though is a bit hand-wavy over why the information is preserved in this new theory...

The abstract from the NPB article is

• 
  It has been found that the states of the 2-charge extremal D1-D5 system are given by smooth geometries that have no singularity and no horizon individually, but a `horizon' does arise after `coarse-graining'. To see how this concept extends to the 3-charge extremal system, we construct a perturbation on the D1-D5 geometry that carries one unit of momentum charge P. The perturbation is found to be regular everywhere and normalizable, so we conclude that at least this state of the 3-charge system behaves like the 2-charge states. The solution is constructed by matching (to several orders) solutions in the inner and outer regions of the geometry. We conjecture the general form of `hair' expected for the 3-charge system, and the nature of the interior of black holes in general.
  

If your institution is a subscriber you can get the full text from here

Re:Hawking radiation

[Anonymous Coward]

Steven had posited... Steven therefore

If you're going to get all Hollywood and refer to him by his first name, you could at least take the trouble to spell it properly.

Re:Hawking radiation

[XaXXon]

If an anti-particle enters the black hole, it LOSES mass.

So we have these virtual particles blinking in and out of existence. One particle, one anti-particle. I understand that when an anti-particle falls into the black hole and the normal particle escapes, the black hole loses mass. Makes perfect sense.

I want to know, why don't an equal number of particles fall into the blackhole while the antiparticle escapes?

Seems you would get a 50/50 distribution leading to no mass change..

I'm sure I'm missing something. Can someone tell me what it is?

Re:Hawking radiation

[ralphclark]

Because the escapeing particle was never in the event horizon to begin with, it can contain no information from within the black hole.

Except that the pair of virtual particles are an entangled pair and if one catches the escaped one and measures its quantum state, one then knows the quantum state of the one that fell in. Catch enough of them and you know about an appreciable fraction of the black hole (in theory!)

Now, how the black hole doesn't gain mass from the anti-particle I'm not quite sure

The energy that was used to create the virtual pair came from the black hole's gravitational field, thus robbing the hole temporarily of mass. For each "virtual" particle that escapes as Hawking radiation, that mass is lost permanently so the mass of the hole goes down, over time. Now remember that this loss can only happen at the event horizon; if the black hole is very large, the tidal force (the gravity gradient) at the event horizon will be weak and thus the rate of particle loss will be very low. For very small black holes the tidal force at the event horizon will be enormous and almost all virtual pairs close to the boundary will separate in this way.

So large black holes will simmer coldly, shrinking only with glacial slowness if at all, and small ones will be hot and shrink very rapidly indeed - finally disappearing altogether in an brief, intense burst of radiation, according to Hawking's theory.

Re:Hawking radiation

[krlynch]

Now, how the black hole doesn't gain mass from the anti-particle I'm not quite sure...

The black hole doesn't gain mass, because the particle that fell in has negative energy. Remember, you can't create energy from nowhere, but you can "borrow" some from the vacuum temporarily ... that's where the virtual pairs come from. They borrow energy from the vacuum, which they have to give back after a time (roughly) Delta T < hbar/E, where E is the energy of the particle pair.

Now, if one half of the pair falls across the event horizon, it isn't coming back. The particle that escapes the hole becomes "real" because it has no one to annihilate with, so it carries off energy E/2. But since you can't yank energy out of the vacuum indefinitely, the particle that fell in had to be carrying energy -E/2 ... which isn't a problem, because it isn't a "real" particle, so it's energy need not be consistent with your expectations from freshman physics.

So, where does that energy E/2 that goes into the escaping particle come from? The only place it can: the black hole. Remember, a negative amount of energy fell in. So the hole has to lose some mass in the process. Which is why we say that the black hole "emits" particles.

The mathematical details are, of course, much nastier than that, but that's the gist of things...

Re:Hawking radiation

[CheshireCatCO]

Careful there. A simple-minded Newtonian derivation gives the correct Schwartschild radius for a black hole, despite having two deep physical flaws and relying on completely inapplicable physics. For that matter, two words: "Bode's Law."

Re:Hawking radiation

[rpresser]

You misunderstand.

A particle and an antiparticle both have a positive mass. The "virtual particle" mechanism means that for periods of times short enough, the measurement of the space right outside the hole is uncertain enough that there "might" be a pair of antiparticles there. So they are there. While they're there, one of them falls into the hole - it doesn't matter which one - while the other gains potential energy from its mate falling in, and escapes. Yaay.

But you can't get something from nothing. Some mass escaped from the vicinity of the hole, so some mass has to disappear from the vicinity of the hole. So the hole loses mass.

How's that for handwavy?

Re:Hawking radiation

[dandelion_wine]

10% troll...
20% off-topic...
70% funny???

you people spent 10 mod points on this snippet of humour?! Scheisse!

Re:Hawking radiation

[Anonymous Coward]

First, virtual pairs are created due to Heisenberg Uncertainty Principle (Et>=h/4pi variant) even in absence of any gravitational field.

Yeah, but they're virtual. You need a horizon to produce real particles from the vacuum.

Second, if a virtual pair can rob black hole temporarily, what mechanism prevents it doing so permanently creating a real p -p pair?

Energy conservation. It works with horizons, because horizons allow one real particle to acquire a positive energy relative to an external observer, and the other (the one that falls in) to acquire a counterbalancing negative energy relative to that same observer -- the fact that the horizon separates the infalling particle from the observer is what allows the particle to have negative energy. The net energy remains zero. If there's no horizon, that can't happen.

Re:Hawking radiation

[Dukeofshadows]

I keep getting 2 + 2 = 5, I think my value of 2 is too large ;)

Not if you're dealing with teenagers. Hence why occasionally 1 + 1 = 3...

Re: Hawking radiation

[Black Parrot]

> Newton can actually say nothing about space around a black hole, at least not anything insightful. He just thinks that the gravity is pretty intense.

Does he ever comment on conditions in the hereafter?

Re:Hawking radiation

[Sivaram_Velauthapill]

So, once the object goes past the event horizon, it's being accellerated _faster_ than the speed of light toward the center of the black hole.

I'm not an astrophysist but I think that's wrong. I don't think anything is accelerated beyond the speed of light--even within a black hole!!! Can someone else shed some light on this? I don't see why something would pass speed of light inside a black hole...

... on the event horizon as physics breaks down.

I think that is not correct either. Physics does NOT break down at the event horizon (from what I know). Rather, physics breaks down at the singularity deep within the black hole. I think the event horizon is well understood. (Actually you may mean something else--in which case you would be right. You are correct if you say that Newtonian Physics breaks down at the event horizon. However, Einstein's Relativity Theory can be used at the event horizon. However, inside the singularity, everything breaks down. We* need quantum gravity, which merges quatum physics and relativity. We haven't developed quatum gravity yet).

Having said that, we don't know what happens inside the black hole. Since nothing can escape, we have practically no observational evidence of anything inside. So all we have are theories.

BTW, someone correct me if I'm wrong in any of this. I am not 100% sure either--since I'm not in the field :(

(* When I say 'we', I'm talking about humanity. I'm not saying *I* am part of this whole thing. I never even took physics in university :| )

Sivaram Velauthapillai

Re:Hawking radiation

[Scott Carnahan]

The black hole doesn't gain mass, because the particle that fell in has negative energy. Remember, you can't create energy from nowhere, but you can "borrow" some from the vacuum temporarily ... that's where the virtual pairs come from.

The virtual particle approach to Hawking radiation seems to be more of a perturbative approximation that has caught on in the popular press than a reasonable description of reality. It may be more natural to describe the radiation in terms of the Unruh effect, which predicts a thermal spectrum around uniformly accelerating bodies - quasistationary objects near the event horizon are bathed in thermal radiation, and this is gravitationally redshifted as it propagates to the distant observer.

This avoids the rather cumbersome notions of negative energy and virtual particles which people tend to find counterintuitive. I have a recent post here which gives some relevant information and links.

Re: Hawking radiation

[richie2000]

Does he ever comment on conditions in the hereafter?

Yes: They have great, juicy apples. He's currently trying to figure out how the snake delivers them but has a theory that it slaps them out of the tree with its tail.

Re:Hawking radiation

[Scott Carnahan]

As I understand it, the idea is that the particle and the anti-particle come into being at the same place, moving in different dirrectsion, and the anti-particle is more prone to being pulled in somehow due it its being the opposite of the other mass in the black hole.

Unfortunately for your theory, particles and antiparticles behave essentially identically near a heavy object, so neither type is favored and (assuming the particle description of the mechanism is accurate - which it isn't) you can expect an equal number of particles and antiparticles to fall in. At least, Hawking's calculations didn't take your proposed mechanism into account.

The particle escapes, generating the black-body radiation, and the anti-particle enters the black whole and collides with a corresponding particle, leaving existance as the original particles came into existance - messed up I know.

If an antiparticle were to enter a black hole, it would add to the mass. If it were to collide with a corresponding particle whilst in transit, there would be some kind of radiation released into the hole, conserving total mass-energy. The perturbative explanation people like to give explains the mass theft in terms of the particle-antiparticle pair "borrowing" energy from the vacuum in order to exist, and the event horizon splitting them before they can recombine, causing the energy debt to be furnished by the black hole.

Re:Hawking radiation

[LittleBigLui]

10% of the mod points fell into a black hole.

Re:Hawking radiation

[orin]

Actually a lot of complex experiments (unless they come up with something totally unexpected like Cold Fusion) - are not reproduced.

The reason is that it is difficult enough to get funding for a complex experiment at the best of times. If you try to get funding to perform a complex experiment that someone else has already performed, you are a lot less likely to be successful.

So although the theory is that scientific experiments are always directly replicated, in most cases scientists don't have the will (why go where someone has gone before) or the funds to do so.

Re:Hawking radiation

[maxwell demon]

Other way:

a = b + c
a(a - b) = (b + c)(a - b)
aa - ab = ba - bb + ac - bc
aa - ab - ac = ba - bb - bc
a(a - b - c) = b(a - b - c)
a = b

Now:

5 = 4 + 1

This is undoubtedly true, and it's the first equation with a = 5, b = 4, c = 1.
Therefore also the last equation is true:

5 = 4

Finally, use that equation with

2 + 2 = 4

and you've got

2 + 2 = 5

quod erat demonstrandum.

Now, to proof that we have really truth, let's proof the central equation (i.e. 5 = 4) again in a completely different way:

-20 = -20 (obviously true)
25 - 45 = 16 - 36 (just rewrote the numbers as differences)
25 - 45 + 81/4 = 16 - 36 + 81/4 (added 81/4 on both sides)
(5 - 9/2)^2 = (4 - 9/2)^2 (used binomic formula)
5 - 9/2 = 4 - 9/2 (took the square root)
5 = 4 (added 9/2 on both sides)

So, agan we have 5 = 4, using a completely diffferent proof. Now, this clearly shows 5 = 4 is true, and therefore also 2 + 2 = 5.

Re:Hawking radiation

[dillon_rinker]

"Proof" #1:
a=b+c (step 1) implies that a-b-c=0
Thus the division that occurs between step 5 and step 6 is division by zero.

"Proof" #2:
Step 4 - (I've an interest in mathematical vocabulary and notation, so this makes me curious. In the US we call this the "binomial" formula. What's your nationality?)
In going from step 4 to step 5, you are misapplying the following theorem:

If x>0 and y>0, and if x^2=y^2, then x=y.

Clearly in step 4, the expression on the right-hand side of the equality is negative. There is no other theorem that lets you "take the square root of both sides of an equation.

[/pedant]

Re:Hawking radiation

[stuffduff]

Beware of zebra crossings.

Re:Hawking radiation

[hesiod]

> trying to debate black hole phenomena with no education save some physics courses in high school.

You elitist twat! I know everything I need to know about black holes from Elementary Science classes, and anyone who says otherwise is itching for a fight!

Of course black holes are proven to be a point in space where everything blew up & opened a hole to the next dimension where there is less pressure, so everything gets sucked up and spewed into it. This next dimension is heaven, and black holes are how you get there, duh! They are God's portals.

Geez, if it weren't for my terrific home schooling, I'd think future generations are doomed. Psh, quantum theory... more like quantum... uh... your mom! hehe, I'm so funny. And original!

stephen lost

[squarefish]

and he looks really pissed about it too.

Re: encyclopaediae

[gnu-generation-one]

"Stephen Hawking and Kip Thorne may owe John Preskill a set of encyclopedias of his choice"

Do they take Wiki?

status of string theory

[microbox]

Is there any hard evidence that string theory is correct?

I'd be holding onto my bet a little longer I think=)

Re:status of string theory

[illuvata]

string theory does not predict anything that could be tested, so there is nno evidence for/against it.
this is also why quite a few people feel its more philosphy than science

Re:status of string theory

[Anonymous Coward]

Responding as I am taking a string theory course from Prof. Zwiebach here at MIT ...

String theory certainly does predict a number of things that are easily testable ... just not right now. For instance, compactified extra dimensions (as SR includes) introduce additional energy terms to simple quantum problems (i.e. "particle in a box" problems, and SHOs). The problem is that these effects are very large; ergo, the energies necessitated to test these theories are somewhat higher than we can accomplish.

Yes, it's a theory, yes it's kinda off-the-wall and feels a bit contrived, but, studying it, I gotta say that it's pretty if nothing else. It's elegant enough and compelling enough - in terms of what it promises to explain - that it's worth following until it's found to actually be wrong.

A quantum theory of gravity might not be so motivating to you, but if you're a physicist, it's worth trying something wonky to get to it. (Speaking of which, Quantum Loop Gravity - also very wonky - is awesome).

And, as for "quite a few people" finding it too philosophical ... well, quite a few people aren't physicists. *shrugs*

Tangle of strings?

[ENOENT]

Yikes! Sounds like all information that enters a black hole turns into spaghetti code!!! The horror! The horror!

Re:Tangle of strings?

[DoctorScooby]

Yikes! Sounds like all information that enters a black hole turns into spaghetti code!!! The horror! The horror!

Now I know where Windows98 really came from.

Of course

[FreeLinux]

This all works on the assumption that you accept string theory in the first place. While string theory may be the darling of astro physicists at the moment, it remains far from proven. If I were Haking, I'd defer payment for a while.

Re:Of course

[Bingo Foo]

String theory has not been proved, but neither has any physical theory. Perhaps you are complaining that unlike other physical theories, it is unlikely that an experimentally accessible test for disproving string theory can be found. This makes string theory not really "science," in the sense that we normally understand it.

Additionally, people's names are conventional rather than scientific, but their legal usage has necessitated their meticulous recording. While it can't be proven, it can be verified beyond a reasonable doubt that the Lucasian Chair of Mathematics at Cambridge is Stephen Hawking.

Re:Of course

[hauer]

No: if string theory is incorrect, it's still possible for every black hole to lose information. Mathur's proof assumes that it applies to a black hole described by string theory. If no black hole is microscopically described by string theory, then his proof doesn't say anything at all about real black holes.

As I said, it does not even make sense to apply the information paradox to the real world (i.e. testing it experimentally). It is a well-defined mathematical statement formulated in a (generalized) quantum theory of gravity. There is no assumption in Mathur's proof concerning about what real black holes are described by.

But in fact, there is much more which can be said. Although the language he uses is string theory, some statements (like the crucial one) are more general than that. Once you assume that quantum gravity exists (without which there is no information paradox at all...), you find some "invariant" statements which are independent of the formalism. It is like the solution of the quadratic equation is independent of the actual formula used to express it.

Re:Of course

[Otto]

Serious question, then. Science is an epistemology reliant on testing, and the knowledge gained from that epistemology. If there is no scientific test for string theory, how can string theory be considered a true theory? It seems it could be, at most, an hypothesis.

You're more or less correct. "String Theory" is just a name. It's possible that it can be tested, it's just that nobody has come up with a way to actually do it yet. It's not really far enough along to be able to come up with a good method to do so, methinks.

But "String Hypothesis" doesn't have the same ring to it. :)

Re: encyclopaediae

[frazzydee]

"Stephen Hawking and Kip Thorne may owe John Preskill a set of encyclopedias of his choice"
I guess so, but only if wiki is what Preskill chose.

Re:Is it me

[microbox]

Maybe the real workings of the universe can't be explained with everyday experiences. After all, quantum stuff and relativity has little bering on hunting, communicating and making little ones, and that's what our brains were designed to do.

Tracing origins...

[Theaetetus]

From the article: Since Mathur's conjecture suggests that strings continue to exist inside the black hole, and the nature of the strings depends on the particles that made up the original source material, then each black hole is as unique as are the stars, planets, or galaxy that formed it. The strings from any subsequent material that enters the black hole would remain traceable as well.

That means a black hole can be traced back to its original conditions, and information survives.

But, if the information about the origins is contained in the strings inside the black hole, that information is inside the event horizon, and can not be observed by anything outside the event horizon. Maybe the information survives, but there's no way to get at it... Unless I'm missing something here? Cosmologists?

-T

Re:Tracing origins...

[Tumbleweed]

> Unless I'm missing something here? Cosmologists?

"Is there a cosmologist in the house? Anyone? My god, get this man a cosmologist!"

Let's get closer...

[Lattitude]

I say we send someone to find out for sure... Darl, you interested?

Re:Let's get closer...

[McBride, Darl]

Yes.

Re:Is it me

[NotQuiteReal]

Yes, it is just you. I knew everything, once - it came to me in a flash of insite... then, incoming email chimed for my attention, I read some spam, had another beer and read Slashdot until something on TV caught my eye.

Now, I forgot what it was that I thought I knew.

As soon as we figure out how to retrieve ...

[burgburgburg]

the information in the black hole, we'll finally find Amelia Earhart. And Jimmy Hoffa. And hundreds of millions of socks. And Duke Nukem Forever.

Re:As soon as we figure out how to retrieve ...

[psoriac]

And Duke Nukem Forever.

Hey, this is theoretical physics, keep your pseudo science out of here!

Re:As soon as we figure out how to retrieve ...

[Bake]

Don't forget the pens!

Of course

[stratjakt]

Information wants to be free!

Yuk Yuk

Shut up, I could have posted a goatse link and referring to black holes.

Tangle of Strings

[Gleng]

bound up in a giant tangle of strings that fills a black hole from its core to its surface

Sounds like the back of my desk!

Yeah, right.

[Anonymous Coward]

... physicists at Ohio State University 'have derived an extensive set of equations that strongly suggest that the information continues to exist -- bound up in a giant tangle of strings that fills a black hole from its core to its surface.'

Sure they do. Physics is the new theology.

Re:Is it me

[Pingular]

Maybe the real workings of the universe can't be explained with everyday experiences. After all, quantum stuff and relativity has little bering on hunting, communicating and making little ones, and that's what our brains were designed to do.
To me, it makes more sense that the real workings of the universe would be incredibly simple rather than complex. Not sure why, it just seems to make sense :)

Re:Is it me

[sisukapalli1]

I am a layman when it comes to physics, but let me put in my layman's two cents in...

Science normally deals with things that we observe, and scientists try to find out the whys and the hows. Once in a while, though there are things that are sometimes theoretically identified before, and it may be a while before such things are actually observed.

S

Re:Is it me

[E-Rock]

I found that in physics, going with 'common' sense or your gut was a good way to look stupid while making it obvious that you didn't review the lecture material the night before.
On the flip side, the math always did a hell of a job predicting the outcome of experiments.

Re:Sweet

[Lehk228]

FAT32 is a pretty good data singularity, goes in but won't come back out

*sob* It must be so sad in there.

[Andy Smith]

the information continues to exist -- bound up in a giant tangle of strings

Aw! Information wants to be free.

You're more right than you think

[Raul654]

Jimbo Wales (founder / benevolent dictator of Wikipedia) was recently approached by a major publishing company about the possibility of a printed version of Wikipedia.

Re:You're more right than you think

[BabyDave]

Jimbo Wales (founder / benevolent dictator of Wikipedia) was recently approached by a major publishing company about the possibility of a printed version of Wikipedia.

Will it come with a free bottle of correction fluid and a pen?

Re: encyclopaediae

[Raul654]

Bzzzt. Wrong.

Re:Simple question maybe

[benna]

Why not consult Official String Theory Web site :)

all those lost by that article, raise your hands..

[The Other White Boy]

*raises hand*

Re:Is it me

[pyros]

Now, I forgot what it was that I thought I knew.

So would you call it an unknown unknown, or a known unknown?

Re:Is it me

[mugnyte]

I don't understand this at all. Our everyday experiences are simply products of the "real workings" of the universe. You may think Newtonian physics suffices for what you need, but your "little ones" wouldn't be able to dream of being an astronaut, science professor, astronomer, or a myriad of other things without these other new-fangled theories.

When we achieve enough proficiency in our understanding to make accurate predictions, and validate them with observations, then publish them, have them scrutinized publicly and repeated, we're making vast improvements to the knowledge humanity holds. The fact that we're in so esoteric topics for new things at the moment just goes to show how valid this system is; we've built a cohesive worldview in physics down to the quantum level. There, mysteries abound, but it doesn't mean we shouldn't be there.

Physicist-speak

[jasondlee]

I think these physicists think that they're so much smarter than the rest of us that they can string a bunch of big words together in a sentence that really makes no sense at all and pass it off on us as the greatest discovery ever, assuming that we're ignorant enough to take their word for it. After reading that article intro, I think they're making a safe bet... :)

It has to be said

[Guspaz]

1. Read up on advanced physics
2. Make bet against famous physicists
3. ???
4. Profit!

Information? Not Matter?

[ackthpt]

In 1997 the three cosmologists Stephen Hawking, Kip Thorne and John Preskill made a famous bet as to whether information that enters a black hole ceases to exist

Slashdot, where information goes to die.

Wow, what a gig

[digrieze]

I have to change careers. These physicists (sp?) have just created the biggest manefestation of a quantom physics illustration ever (namely scrondiggers (sp?) cat). The black hole is the box, the information entering the event horizon is the cat. Anything at the singularity is not observable and is therefore in a permanent state of flux between states (not really, but our ignorance of what's going on creates that condition). When we make observation our predispositions on the data influence the observation and change the reality. In other words YOU CAN'T BE WRONG NO MATTER WHAT YOU SAY!

Is there some way I can get this gig?

Almost - wrong bet though

[Raul654]

Hawking has made several bets. You are thinking of his naked singularities bet (A naked singularity is a black-hole without event horizons) Hawking bet Roger Penrose(?) a subscription to Penthouse (I think) that they could not exist. He lost.

Re:Almost - wrong bet though

[frozen_kangaroo]

I was pretty sure that it wasn't encyclopediae either ! (it was though.) For the truth about hawking's wagers see here (6th paragraph down):

In 1975, he bet Kip Thorne a subscription to Penthouse (the loser would get it mailed to his home) that a celestial mystery named Cygnus X-1 would turn out to be a black hole.

Re:Simple question maybe

[Anonymous Coward]

A very tiny dimension all curled up on itself as opposed to extending to infinity (like we're typically familiar with). If a foam in a bubble bath is the whole universe, a bubble in the foam might be analogous to a string. Space is soap, we're not allowed to see it directly, but we can see its effect.

String theory has modest successes with some things, and monsterous problems with others. It's essentially built to explain why gravity is so weak. At distances smaller than strings gravity is as strong as all the other forces. But it doesn't overwhelm everything at large scales because gravity is the only force which can see the strings, and so it leaks off into these other dimensions untimately becoming very dilute.

The hope of theoreticall physicists is to unite gravity with the other forces, understanding everything about it's divergance, hopefully uniting quantum electro/chromodynamics with general relativity creating one theory to explain them all, and, in mathmatics, bind them.

Black holes have hair

[B2K3]

I had a conversation about this very topic this afternoon. I even uttered the phrase, "Thank God black holes have no hair!" I'm glad I didn't bet on it.

On a side note, what would be a good bet for physics today? "I'll bet you the Google cache..."

And remember, not only am I president of the hair club for black holes, I'm also a client.

Re:It was a Playboy subscription...

[kfg]

Here is an actual reproduction of the bet document you are thinking of:

Hawking/Thorne bet

Ain' the web grand?

Yeah, Stephen lost that one. Word has it that Kip's wife was a bit miffed about the payoff.

KFG

Oh really, come on, get a clue!

[Jerf]

It is often... though not often enough... pointed out that the singular of "data" is not "anecdote".

Similarly, "fact" is not merely an emphatic form of "theory".

I might as well theorize that black holes don't exist at all; who owes what now? Oh, right, nothing changes, because theories aren't facts .

Mick Ohrberg, why don't you grow out of Physics Fanboydom and take some time to learn some real stuff? For starters, why don't you being with Science 101 and learn the definition of "theory", and "equation", and other such basic terms?

Jim Carrey feels Hawking's rage

[B2K3]

The pictures prove it.

I love you, Stephen Hawking.

What it doesn't say.

[DynaSoar]

I can buy that the information survives and continues to exist inside the Schwarzchild radius.
But when they say:

"The strings from any subsequent material that enters the black hole would remain traceable as well. That means a black hole can be traced back to its original conditions, and information survives." ... they're going to have to explain a bit harder just how it is we're supposed to be able to extract that information back out through the event horizon. Whether it continues to vibrate on linked strings or vanishes in a puff of nonreality makes no never mind if you can't get it back out.

Re:Simple question maybe

[Anonymous Coward]

Look here for a series of clips discussing the string theory, the 'M' theory, and a lot of stuff that led up to it.

It depends on what "ceases to exist" means....

[HarveyBirdman]

...if I may wax Clintonian.

Maybe it exists on the other side of the event horizon, but I thought string theory tells us that things like event horizons shield the universe from singularities and other discontinuities. The information cannot be retreived, therefore, from the point of view of the universe, it has ceased to exist.

What's the difference, really, between destroyed information and irretrievable information?

Re:Too bad for Kip Thorne

[benna]

Actually that was a different bet between Thorne and Hawking which Hawking conceded to Thorne years ago. It was a bet on whether Cygnus X1 was in fact a black whole. Hawking bet it wasn't and Thorne bet it was. Hawking said he really did think it was a black hole but he wanted to win something if he was wrong so as to be less depressed about it.

Mathur's tests

[trip11]

I've actually had Mathur for classes as I'm an undergraduate at Ohio state in physics. His tests really are not all that brutal as he is both an amazingly smart man and a good teacher. He has this dry humor that you have to pay attention to to get. Amusing quips include:

"It will be a big piece of fun" (talking about deriving equations)

"thats a rather large force" (after mentioning that the force to pull two pieces of a capacitor apart could lift the city of columbus)

If you get a chance to meet him, don't pass it up. He's a great guy

Black Hole Interior

[whig]

Perhaps the information survives in the black hole interior. Physics infers a black hole by an event horizon, but that does not necessarily imply a singularity. On the other hand, if the interior is considered as a "universe" with its own set of physical laws and structure, this conjecture could be quite relevant.

For a somewhat handwaving explanation of what I'm talking about, take a look at this hypothesis.

Re:Is it me

[be-fan]

I think the point is that while you may be able to understand physics, at an abstract level, can you understand it at a concrete level? Our real world experience is mainly a matter of the concrete. Things we can see, and touch, and hear. I drop something, it falls down. I push something, it moves, etc. Physics, however, is completely abstract. You can't see an atom --- you can't even visualize what it would look like if you could see it. The only way to truely understand it is to understand the mathematical model of it. But even when you have that understanding, you don't have something equivilent to your real world experiences. You still can't see it.

Isn't this simple physics?

[dacarr]

I mean, one of the laws of energy states that it cannot be created nor destroyed, only converted, and the same *generally* goes for matter (lacking antimatter). Yes, black holes can theoretically alter reality, but if they are effectively hypercompressed neutron stars, the alteration is that you get one hell of a monstrous compression algorithim.

So for the quantum astronomy and astrophysics geeks, am I missing something?

Re:Isn't this simple physics?

[1s44c]

You are missing something.

Noone doubted the energy continued to exist.
The bet concerned the patten of information held by the matter/energy. The questions was if you encoded something in a patten of laser light and sent that into the black hole would the encoded information continue to exist? ( given that no record of the data sent exists except that encoded in the light. )

Google for holographic universe, it's interesting stuff.

Blackt holes shown to compress losslessly.

[Canthros]

Decompression support expected in next WinZip release.

Re:Blackt holes shown to compress losslessly.

[Creepy Crawler]

That stupid winzip. PowerArchiver has ALWAYS had BlackHole (de)compression. Good ol' .bh files. ....except they didnt look like strings..

The conclusion may be wrong

[jd]

I can prove that if you pour information into Congress, you end up with a tange of red tape, which is similar to a superstring. (Red tape is used to hold things together that would otherwise fly apart; red tape requires at least 10 more dimensions to exist; and there is some evidence that particles of beaurocracy have negative gravity.)

However, there is no proof that any of the information survives, after being caught up in red tape. Indeed, all evidence so far suggests that it does not.

(Beurocracy particles are a subclass of Strange Quarks that have beeen influenced by a politic Ion)

Woooosh!

[Barlo_Mung_42]

That's the sound of this article flying over my head.
"bound up in a giant tangle of strings that fills a black hole from its core to its surface"?

So it's really just a tightly wound baseball?

Re:Is it me

[mindstrm]

Part of the problem is the language used to describe these things.. the general approximations they make only really make sense if you understand a lot more background..

On the surface this might all seem like philosophical banter... but that's just what the news prints. What is behind this is tons of chalkboards and computers full of equations that fit modern theory.

Remember, we don't HAVE a theory of everything yet... i'ts not like everything is perfect, and scientists are trying to make things up to look smart.. there is a point where our current equations don't add up, don't make sense.. and that's where these guys are working now.

superstrings, quantum gravity, etc.. these aren't whimsical sci-fi dreams.. they are where science is currently trying to figure things out.

Next on "Ask Slashdot"

[the cobaltsixty]

"What's the most expensive encyclopedia you've ever seen?"

Re:Next on "Ask Slashdot"

[Daniel_Staal]

A complete, signed by the authors, hardback edition of Wikipedia.

(I'm sure you could do it...)

Proof.....

[vwjeff]

I don't know about you but I need physical proof of this. I say the winner must travel to a black hole and prove that matter exists within the hole.

Re:Double-Dog dare you...

[smart.id]

Steven Hawking is a parapalegic... I don't know how it would work with him.

Re:Is it me

[wass]

ike they're so determined to make something make sense, they blindly look for something that'll fit the problem, even if it's obvious that it's probably not right

I actually recently responded to a similar accusation against physicsists, and you can read my reply here . That response has more examples listed of 'kludges' in physics, but I'll talk about a few in more depth in this post.

What you've just described is known as phenomenology. In other words, trying to come up with some sort of basic theory to match the given data. Examples include Planck's original quantizing of radiation into discrete quanta, which turned out to be right. Another example is the Landau theory of 2nd-order phase transitions, where one builds a power-series expansion of the free energy in powers of something called the 'order parameter'. This is a total hack, but in many cases can adequately describe phase transitions (including superconductivity).

In fact, there are many kinds of physics theories, some termed 'macroscopic' in which case they're phenomonoligical, and describe what's going on, but don't adequately describe the 'physics' of the system. Then there's the microscopic theories that talk specifically about particle interactions, and follow directly from quantum mechanics, statistical mechanics, E&M, etc. The goal is to make these two approaches mesh.

For example, superconductivity could be described fairly well using the Ginzberg-Landau expansion, where the order parameter described above is complex, instead of real. Many things can be described this way, including Josephson Junctions and fluxoid quantization of superconducting loops. (Ginzberg just won the Nobel Prize in physics in 2003. Landau, if he were still alive, would have probably won it too, and it would have been his 2nd physics nobel prize). This approach worked fairly well, but physicists weren't sure why that was.

But then in 1957 Bardeen/Cooper/Schrieffer came up with the BCS theory of superconductivity, which explicitly describes how the electrons can pair up into Cooper pairs. Electrons want to repel, but in the right crystal lattice an electron-phonon-electron interaction (ie, a local distortion of the lattice) can produce an attractive interaction. BCS describe how this attraction comes about, how the energy gap forms, and how the electron pairs can carry a resistanceless supercurrent. BCS won the Nobel Prize in Physics in 1972.

This was microscopic vs macroscopic development of superconductivity. Two years later, physicist Gor'kov was able to show that the Ginzberg-Landau theory comes as a limiting case of the BCS theory. Hence, microscopic meets macroscopic, and everybody's happy.

So yes, physicists do look for something to fit the problem, but they don't just stop there. They also try to make those hacks or kludges match up directly from physical laws of the universe. That's what physics is about.

Re:Some questions from a non-physicist

[Anonymous Coward]

Tunneling effect - a particle has a certain chance of overcoming a potential barrier even if it doesn't have enough energy to do so. Why can't a particle from within a black hole escape it similarly?

Real particles can't tunnel outside the light cone (faster than light), which is what would be necessary to get out of the horizon. If you're talking about the vacuum production picture of Hawking radiation, there is a sense in which it can be interpreted in terms of tunneling.

Accumulation of mass/energy. What exactly prevents a black hole from exploding, after accumulating enough mass - what makes them so stable?

Why should it explode? There is no limit to how much mass a black hole can contain. The more mass you dump in, the bigger it gets.

Is it possible that the Big-Bang was an explosion of a huge black hole ?

Not really.

If a half of a quantum-entagled (EPR) pair enters the event horizon, can it somehow be used as a "probe" ?

No. Quantum entanglement can't be used to transmit information, regardless of whether there is a black hole around.

See also sections 9, 10, and 11 of this FTL FAQ.

Tools already available?

[Snork Asaurus]

... information continues to exist -- bound up in a giant tangle of strings that fills a black hole from its core to its surface

Like the WWW? So, finding information trapped in a black hole sounds like a job for ... (ta-daa) ...: Black Hole Google! Boldly going where no search engine has gone before...

Re: encyclopaediae

[Black Parrot]

> As far as accuracy - that will come with time.

My faith in that is starting to slip. I recently ventured out into some pages I hadn't previously been watching, and found several pages whose history shows that they have a k00k "squatter" who watches the page and insists on sticking his idiocy back in no matter how many people come along and correct it, whingeing all the while that everyone else is pursuing some dishonest agenda.

Futurama Quote

[mr100percent]

Fry: So, you guys want to see my Fry-hole?
Stephen Hawking: I call it a Hawking hole. Fry: No fair! I named it first!
Stephen Hawking: Who is the Journal of Applied Physics going to believe?.

Re:Some questions from a non-physicist

[Kiryat Malachi]

1. Tunneling - because to escape a black hole requires exceeding the speed of light. The reason Hawking radiation can get away with it is because one particle in the pair is created just outside the event horizon and gets a kick outward from the annihilation of its partner.

2. Gravity. An explosion cannot push matter at or faster than lightspeed. I guess, in theory, the center of a blackhole could explode continuously, but we'd never know because nothing would ever exit the event horizon.

3. I have no idea. Hell of an interesting question, though, and one that I bet there's some debate about amongst physicists - basically, you're asking is it possible to transmit information faster than light (being that FTL is the necessary condition for energy/mass escape of a black hole). This one is way beyond my handwavy quantumness.

Ironic Science

[Ralph Spoilsport]

First: I think String theory is probably correct HOWEVER:
Second: I can't see how you can possibly test any of this.

If you can't test it, then it's just a likely story. It might be a more likely story than saying little green elves did it all, but in essence, it;s not that different.

Tangles of strings - Suuuure.

As I said, it probably is true, and string theory is a lot cleaner, but damn - what are you going to do? Crack open a black hole to find out?

We. don't. think. so.

It strikes me as what Horgan calls "Ironic Science".

RS

Re:Wait a second..?

[maxwell demon]

The very foundation of this shrinking black hole theory depends on this mind boggling mass.

This is where your mistake lies. The very foundation of the black hole is in it's mind boggling mass density. The absolute mass is important only in formation, because with too little mass gravitational forces are not able to compress matter enough to create the black hole.

You could get a black hole (complete with event horizon and Hawking radiation) by compressing earth into a radius less than about 9mm. Indeed, the less mass a black hole has, the smaller it is, and the larger the space curvature is on it's event horizon. Therefore all effects coming from space curvature are stronger for them, which also includes Hawking radiation. This especially means that finally black holes "explode": the more it radiates, the faster it gets smaller, and therefore it radiates even more in even shorter time scales, until it radiated it's complete mass away.

Of course, as soon as the black hole gets down to a size near the planck length (a mindboggling small length where quantum gravity effects are huge), we already know that all semiclassical reasoning must fail, therefore we cannot really say anything about what will happen at the last moment of a black hole, until we have a successfull theory of quantum gravity (or have watched black holes exploding, of course).

Re:Some questions from a non-physicist

[NonSequor]

One correction. Quantum entanglement can be used to transmit information, but only if you already have a classical (slower-than-light) information channel already running between the two places. Basically, if Alice and Bob each took half of an EPR pair then later if Alice has a qubit she wants to send Bob, there is a method by which she can perform operations and measurements and then send the results of the measurements to Bob who then acts on his half of the EPR pair which becomes the qubit that Alice wanted to send. There is no way to do this without the classical information channel though.

is it an encyclopaedia?

[MozillaFireBird]

In 'Brief History of Time', Hawking talks about a bet for one year subscription to 'Penthouse'. Any idea about that bet?