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Doubting the Existence of Black Holes
The Good Reverend writes: "It seems that there's a growing movement that doubts the existence of black holes, going against most of the rest of astrophysics. They suggest the existence of gravastars, "star-size agglomerations of "wavelike" substance" (space-time fabric, if you will). Different scientists claim to have created the "wavelike substance" in a lab, called Bose-Einstein condensates." I understand gravastars taste terrific with cream cheese and red onion.
is this a major breakthrough in astro physics or just a slight modifictaion in semantics?
how does one change his
I think i felt my brain blow up into many small pieces and then collapse in to a newly formed black hole.. or whatever they are calling it now... owww i need some asprin...
will cure all doubt...
Oh, Holes...
NM
Who run Barter Town?
These gravastars are probably quantizable, where blackholes aren't.
I hope none of these people get the idea to try to make a little black hole in a lab somewhere, this stuff sounds dangerous to play around with in a laboratory!!!
Would that be rather like neutron stars? My understanding is that current orthodox astrophysics models meutron stars as either a Bose-Einstein state, or as (in effect) a single, very big, neutron. (Or, er, are those the same things?) C'mon astrophysicists, enquiring idiots want to know! ;)
"None are more hopelessly enslaved than those who falsely believe they are free." -- Goethe
I think these people are going to run up against the principle Metatheorem of Quantum Gravity: All theories of quantum gravity are wrong.
Tarsnap: Online backups for the truly paranoid
...whether a theory, unifying the gravitational force with the other three fundamental forces, would be at odds with the existence of black holes?
:)) how a quantum view of gravity would affect theories on black holes and the birth of the universe. Basically my question is: If gravitational attraction is carried by a particle (the graviton) as is conjectured by many scientists, then how can one of these escape from a black hole any more than another particle?
:)
I have often wondered (but never had the time, inclination or intelligence to go find out
I guess that either:
a) It can't, ergo black holes don't exist;
b) It can, and Einstein was wrong somewhere;
c) There is some effect similar to the X-ray "emissions" from black holes, whereby the particles appear to come from the black hole but actually never cross its event horizon.
Which just goes to show that a little knowledge is a dangerous thing.
These sigs are more interesting tha
If this is something that they can "create" in a lab, then perhaps it's small enough to be the oh-so-difficult-to-detect dark matter that has eluded science so much recently? It seems a little more plausible that "micro black holes", or whatever the theory of the week is.
"I have never let my schooling interfere with my education." - Mark Twain
Sounds to me like they're just quabbling over the name of the "black hole". These are our best and brightest?
Skiers and Riders -- http://www.snowjournal.com
Correct me if I'm wrong, but as far as my knowledge goes, I thought both blackholes and the Bose-Einstein condensate are supported by/derived from Einsteins theories.. Isn't there some sort of compatibility between the two? I'm sure Einstein will have studied that, considering both phenomena have the same characteristics to an extend where they are both used to explain the same physical phenomenon..
You do not exist. Go away.
They've made it in a lab huh? Boy I bet that's the lab across from where I work. This explains SO much about the black hole that is my wallet and associated credit cards. . .
Find out about my new childrens book: SS Death Camp Criminal Batallion Go To Monte Carlo For The Massacre
"It's almost impossible to form a black hole this massive in a binary system"
It is apparently difficult to prove the formation of Black Holes through physics. Methinks either black holes don't exist OR this gives more weight to the creationist theories.
"What is not posible with man is possible wiht God"
Hmmz... I see this more as 'OK-news'. It's like ok, but you cannot really form a discussion about it. Nice to know, but what do you want me to say about it?
:))
(Okay, okay, it kicks ass, but does it change anything for us in the near future? Guess not... heh, too bad!
"Claim" is hardly the correct word, since it is not disputed (to my knowledge). Last years Nobel Prize in physics was awarded to the first experimenters who created this sixth (depending on how you count) state of matter. The existence of Bose-Einstein condensate is not in itself any challenge to black holes.
The article states: Calculations show that a black hole would contain astoundingly more "entropy" than the matter that fell into it
If the article was less sensationalist, they would have mentioned that there are also calculations based on Hawking radiation that show the entropy of a black hole to work out perfectly. Some say the entropy is wrong, others don't. Also, referring to singularities as "paradoxes" seems strange. One would rather not deal with them, of course, but paradoxial? Nah. Since they are always hidden and cannot be reached in finite time, the philosophical question is whether they even can be said to exist in the same way as other things exist.
The article also does not increase in credibility, when it refers to the uncertainty principle as "eerie" and to black holes as "spooky" and "scary".
What about gravastars then, are they for real? Dunno... Most theories are at the fringe for a good reason, though.
Opinions stated are mine and do not reflect those of the Illuminati
..that reading the science section of /. is like reading New Scientist with a two week delay?
Sorry, but
...WTF?
I understand gravastars taste terrific with cream cheese and red onion.
The gravistar supporters fail to realize that their entire argument lies on Einstein's second generalized form of energy-condensation theory, which merely takes into account 3-dimensional wave function of the hamiltonian space-time over a negative-sequenced domain of the time-vector field. This is clearly false, as one can see in the Bose-Millikin experiments involving the 3 spheres separated by a small distance.
The spheres came into contact ONLY when the time-vecor field had a maximum at at least 4 points, but no more than 6. This will never occur in a collapsing star because the Tihs-Llub equation predicts a minimum of 8 such maxima points.
The only way to explain this is to either decide that gravity is fundamentally different than the other 3 forces OR that black holes don't exist. Or both.
Whether or not the matter condensed into some kind of Bose-Einstein condensate or collapsed to a point is entirely academic because whatever it is would still be within the event horizon, and would act the exact same way in either case.
-- Give me ambiguity or give me something else!
My first opinion of this hypothesis is that it is a big stretch. First, a little background.
A very massive star has a very massive gravitational field. Through its lifespan the star does not collapse under its own weight due to the ongoing fusion reaction which powers all stars. When the nuclear fuel finally runs out, the star begins to collapse inward. (For those of an astronomical bent, yes I am skipping over some details as to the various stages of fusion that grant temporary repreives to the collapse).
As a star collapses, the atoms that make up the star are packed more and more tightly together. If the star is massive enough, the electrons and protons are finally merged together to form neutrons. The neutrons then pack together more and more tightly until the repulsive force between the neutrons prevents further collapse (for stars not quite massive enough to become black holes) or the neutrons themselves crush in upon each other into even more degenerate states of matter. As far as we know, once you pass this point there is NO OTHER REPULSIVE FORCE available to keep the collapse in check. The star collapses all the way down to a single mathmatical point.
The second bit of background we need is an explanation of Bose-Einstein Condensates. First, you need to know that all particles can be described as waves. In the macroscopic world in which we live our daily lives, the waves are such tiny little packets that we don't perceive them as anything more than particles. However, on the microscopic level, particles begin to really demonstrate just how wave-like they can be. When a group of atoms is collectively cooled down to very close to absolute zero, the behavior of the individual atoms become linked together and they begin to act a single atom. (The wave functions describing the individual particles merge). It is a funky-cool state of matter that is regularly used now in a range of physics experiments.
The hypothesis in the article on black holes is that spacetime itself can undergo a "phase change" not unlike the way that matter can go from solid to liquid to gas -- or even (in labs) to a Bose-Einstein condensate.
The important thing to note here is that
(a) no one has ever seen a phase change in the fabric of spacetime (I'm not sure the concept even makes sense, personally).
(b) The authors are NOT saying that the black hole's stellar material BECOMES a Bose-Einstein condensate -- they are saying the the fabric of spacetime itself becomes the "spacetime-equivalent" of a Bose-Einstein condensate (whatever that would be!).
My feeling is that while it *could* be the case, basically they are trying to dream up a totally hypothetical new phenomenon (phase changes for spacetime) to find some way to get rid of black holes in physical theory. I don't see that the new phenomenon has any grounding in theory or observation -- it's strictly hypothesized for the end result -- and is therefore very unlikely to be true.
Now, that's NOT to say it CAN'T be true. However, I expect their may be dozens to hundreds of other such hypothetical creations designed to counter the infinite collapse that supposedly occurs in black holes -- the concept of a black hole is "offensive" in physics because you end up with a big "divide by zero" error in the universe. We do, however, have good evidence for the existence of black holes, so no matter how much physicists hate what they do to the math, we may have to simply accept them.
Life is short: void the warranty.
It looks to me like they are saying that,
Black-holes are singular in them selfs, e.g. they exist only in one wave
,but have dimension relitive to evrything else.
The 'Force' produced by the singular wave that is the black h0le is the force of dimension.
That is to say that a black hole is one plank? length but the size of this plank appears to be a lot bigger in relitive terms.
The same thwory could be applied to the spped of light e.g. as matter reaches the speed of light, the relitive plank lengths of things arround it are smaller, and the matter appears to be smaller to anything that looks at it. at the speed of light the matter becomes one wave, having a plank length of 1 but a size of more than one plank relitive to evrything else, this size is force.
First we faked moon landings, now we've faked black holes! Is there even really any stars at all up there or is it just a bunch of lights in a big dome?
As a rock-in-roll Physicist once said, No matter where you go, there you are.
They're always being chased by the cylons.
"Technology.....the knack of so arranging the world that we don't have to experience it." Max Firsch
New Gravastars - part of a complete breakfast when served with fruit, juice, and the Milky Way.
Bose-Einstein Condensates are completely unrelated to General Relativity. The theory which predicts/explains Bose-Einstein condensates is Statistical Mechanics when applied to Bosons. Numerous Stat. Mech. books include this as an example, my favorite is Statistical Mechanics by Pathria.
On the other hand, black holes are a result of the Einstein equations from General Relativity and are a result of the energy stored in the gravitational field affecting the gravitational field (don't think too hard about that or blood will shoot out your nose). It is worth noting that gravity is the only one of the fundamental forces which does this. Anyway when a sufficiently high density of mass ends up in one place (a very small place) a black hole forms, which is not quite a singularity as commonly described, but something which actually has some radius. Close to the surface of the black hole there is a whole bunch of time dilation and spacial distortion so that if you watched something fall into a black hole you would never see it enter the black hole, it would just get really flat. Inside the black hole the sign of the time coordinate and the radial coordinate of the space-time tensor, as defined in special relativity, are both reversed. This has the effect of allowing someone to travel back and forth in time (provided they survived entry), but can only move towards the center of the black hole (therefore not violating causality).
Now for how black holes are formed. As stars burn out their fuel, they colapse, fuse heavier elements, colapse, fuse heavier elements... After a while, they run out of stuff to burn. When this happens they finally collapse, and the result is determined by the mass of the star. If they arn't too heavy they will end up as a collection of protons and electrons held together by gravity. If they are heavier their gravitational forces will force the electrons and the protons to merge into neutrons resulting in a neutron star (which are really interesting in their own right). Finally, if they are really really massive the effect preventing the neutrons from colapsing into a neutron star, the Pauli Exclusion Principle, is insufficient to prevent the formation of a black hole. I think the original article is saying that the bose-einstein condensate (which applies to bosons, not fermions like neutrons) would up the amount of mass required for the final colapse by introducing some sort of boson-like state between the neutron star stage and the black hole stage. For this to happen the quarks and gluons making up the neutrons would have to be rearranged into bosons and that this would only be energetically favorable at the extreme high pressures from an object more massive than a neutron star.
All that isn't to say that black holes arn't freaky, but General Relativity needs to be disproved and some alternate explaination of the giant black holes at the centers of just about every galexy needs to be found before we say they don't exist (Achim's Razor).
A black hole is a term for a mass that is compact enough that it lies within an event horizon. Heuristically speaking, light cannot escape because the escape velocity from the object is faster than the speed of light, so it appears dark.
In General Relativity, given a sufficiently large mass (say, a 10 solar mass star), there is no source of rigidity strong enough to withstand gravitational collapse, so black holes will eventually form.
Big stars exist, so avoiding black holes requires either a new theory of space time (or gravitation), or a new type of matter.
These guys have opted for a new type of matter,_analogous_ to a Bose-Einstein condensate. The existance of Bose-Einstein condensates in the lab for regular matter (routine, now), says nothing about whether this exotic matter exists out there.
This is still pretty wide open from a theory vs experiment sense. Most claims for black holes are really observations of dense collections of matter. Some would be black holes for sure in General Relativity, but this is no proof.
The best source of proof for black holes will probably come from detection of Gravitational waves from their formation, which should come in the next few years from experiments such as LIGO or LISA .
...Javastars
Javastars run slower than gravastars but will work in any universe.
For me it all boils down to the question of the mass of light. If light has so small mass that it is barely affected by gravity then i dont think black holes exist. If it do has some amount of mass it could be affected. But how big can a certain mass of materia be before it reaches critical mass and explodes? Is it big enough to affect light? Can gravity be strong enough to hold such extreme powers at bay as would have to exist inside a black hole?
HTTP/1.1 400
Talk to an astrophysicist, especially an X-Ray or Gamma ray astrophysicist. They will set you straight.
This is one of the worst science articles I have ever read. Anyone who would put the word entropy in quotation marks doesn't know a goddamned thing about how the wolrd works, let alone the universe.
SetupWeasel
As I understand it the current best guess at the theory of everything is called M-theory
m en s.html)
(http://www.fortunecity.com/emachines/e11/86/di
which talks about the universe being a single membrane, of which all matter (and energy and everything else) in the universe is part. This exists in 11 dimensional space.
M-theory is an evolution of string theory
The theory goes that gravity is seepage from another universe a small distance away (like a few mm) in 11 dimensional space.
They believe that in essence gravity is the same strength as the strong nuclear force but what we feel is the translation of that into just 3 dimensions and acting at a short distance. This would then imply that the limit on gravitational forces would be of the same order and would occur when two such universes where very close.
Incidentally M-theory also can explain the big bang as a collision of two membrane universes.
You can't win Darth. If you mod me down, I shall become more powerful than you could possibly imagine
What's that, you say? Oh, gravistar. Nevermind...
Chris Beckenbach
It's also a spelling mistake.
It's gravistars, not gravastars.
There are a lot of things possbily wrong with the theory, but then Black Holes have some problems with them as well.
New Scientist had about three weeks ago something on this, which is fairly simple to digest.
Good news is that there is a way ot tell the two phenomena apart. So it's at least disprovable.
No more alternate universes? No more time travel?
I hope this gravastar theory is disproved soon, it's no fun at all.
Some have said theres a ring of fire in a black hole, in which you dont get crushed, you just get trapped.
Others claim you get crushed out of exsistance, we really dont know anything about blackholes until we send something into one.
As far as creating blackholes in labs, do they even count?
If you use Linux, please help development of Autopac
How can space-time change? What is the change over? If I change position in space, I do so over time. If I plot this change, I get space-time. Space-time by definition has no movement.
Oh, never mind. What's the point.
Haven't I seen this before on slashdot?
Any sufficiently advanced influence is indistinguishable from control.
They have made blackholes in labs before, its not dangerous because they phase out of exsistance almost instantly because they are so small
If you use Linux, please help development of Autopac
I would like to point out that posting an article before the team concerned has published their paper is very bad news for the team.
What often happens is that the team becomes doubted initially because they haven't published the paper, or because the article writer doesn't know what he/she is writing about. Sometimes it blows up in their face, ala Cold Fusion.
I would also like to note that the technical quality of the article is poor and shows a lack of understanding of the subject matter.
For example:
"The location of a particle constantly varies according to a statistical pattern -- one moment it's here, another moment it's there"
This shows a complete lack of understanding of the uncertainty principle! The particle has no 'position', and as such it can't be here one moment and there the next. Its position-space wavefunction is the best we can get.
There are also quite a lot of claims made in the article that really deserve a reference - hence the problem if the only reference is unpublished - in particular I would like to see an argument for why spacetime undergoes a phase transition inside the black hole. What theory predicted this? Certainly not General Relativity, which is what predicted black holes in the first place. What modifications must be made? How is quantum mechanics used in this setting?
Note that quantum gravity is still an unsolved problem, so I'd be surprised if this prediction turns out to be spot-on. But I can't tell for sure since the paper is unpublished =(
I always like articles like this. Mostly because the only heresy in science is parochialism (in the third sense re: dictionary.com). Come up with an interesting idea, support it, research it, and answer criticism. This is especially fun for this hypothetical stuff beyond the edges of the singularities.
Of course it isn't that elegant in real life but, hey, I can dream can't I?
What is music when you despise all sound?
Is this just a refinement of the previous coverage by /., or have they changed their minds? I guess the idea of a singularity has been knocked enough to be ruled out?
"Area man wonders: if there are no black holes, where do all the pens and socks disappear to, and where do coat-hangers come from?? I've never bought a coat-hanger in my life, yet they always magically appear. Whenever I move to a new appartment new coat-hanger's appear, they must come from somewhere. There must be some kind of weird extra dimention thing happening..."
Ossama bin laden, surprised by this turn of events was quoted as saying, "If black holes don't exist, then where does allah cast the infidel's souls when the are killed? ah but if there is a wave like substance, this could relate to some kind of lake of fire scenario, and there by prove that I am not just a fanatic nut"
I don 't think you can easily explain the large concentration of mass mesasure in the nuclei
of active galaxies (AGN), with such thing.
OverLord
" Rather, this substance would be the underlying "space-time" fabric of the universe, which, as Einstein showed long ago, "curves""
...
Aaaaaargh. This article reads like BBC2's _Horizon_ programme. All "these people discovered some random idea, aren't they wonderful?" BS explaining why "blue" is a colour to the clueless population never mind concentrating on the idea to hand at all - apparently Bose-Einsten condensate is somehow the "fabric of the universe"?
I said way back at Uni, and will say it again: I don't want to know whether Einsten *liked* a particular idea, I want to know the *idea* and I'll make up my own mind. Give me equations, keep the pop-psych AWAY.
~Tim
--
Rushing on down to the circle of the turn
"I understand gravastars taste terrific with cream cheese and red onion."
"Tastes Great!"
"Less Filling!"
And what Bose-Einstein condensates have to do with it is murky at best. Like a BEC but made of space-time rather than atoms? What the fuck is that mealy mouthed shit supposed to mean?
Insanity is the last line of defence for the master diplomat. But you have to lay the groundwork early.
Black holes required two physical concepts: (1) velocity & acceleration are tied to mass (Galileo & Newton), and (2) the speed of light is finite. Both these concepts were worked out in the 1600s. Soon after someone did spectulate about bodies massive enough to trap light. Doesn't require Einstein relativism.
No, I think Gravastar was that 80's video game from Williams Electronics where the big crystalline space monster chases your ship around... kinda looks like a big disembodied Skeletor or something.
I think it would be cool if there were a bunch of those things floating around space instead of black holes. Rawwwrrrr!
I take drugs seriously.
Graviton is a hypotetical particle which may not exist. As far as I know it makes some calculations easier. However, according to Eistein, gravity is just the curvature of space-time. There is no graviton or any particle which causes gravity.
If Eistein is right then an Anti-Gravity device cannot be made, because there is no particle to shield. However, as far as I know it is an ongoing debate in the science community whether a particle or the curvature of space-time causes gravity.
Government cannot make man richer, but it can make him poorer. - Ludwig von Mises
Doubts?
Where were you hiding all that time?
Or was it "pseudo-science" from the beginning?
Frankly, the whole scientific community had turned into a country club.
they just don't have REST-MASS ,and they cannot be at rest.
the 4-vector which describes them is (k,0,0,k) so you see, the mass-energy part is != 0.
Working for necessity's mother.
A more concise and to the point article is available at:
h ol es/index.html
http://www.cnn.com/2002/TECH/space/01/21/black.
This is sour grapes, but, geez louise, I submitted this item in January and had it rejected.
---Any philosophy that can be put "in a nutshell" belongs there.---
Bose Einstein condensates are routinely produced in laboratories the world over. They have to be condensates _of_ something though. In the lab, they're usually supercold helium.
In a gravsatr, the proposal is a bose-einstein condensate of spacetime itself. Same mathematics, very different reality. Definitely NOT produced in any earthly laboratory.
using an accurate measuring technique involving mossbaur effect the difference in momentum of a photon rising several meters was actually measured: divide that with g and you get the mass.
an amazingly cool experiment, though somewhat old.
so this means gravity does affect light (though there are much simpler experiments which showed that, as early as the 1920's, I believe)
Working for necessity's mother.
So do we now beleive in the existance of ether again?
I believe that it was not Einstein who first noticed that the GR equations yield solutions which have spacetime singularities, i.e. blackholes. This was first found by Schwartzchild.
Einstein's equations do not predict blackholes. Blackholes are simply compatable with his equations.
This does not mean that blackholes may be incompatable with other physical laws, notably those of quantum mechanics/field theory and those of thermodynamics, which is why it is theoretically interesting to try to derive the quantum and thermo properties of blackholes to find either a contradiction or an interesting property which one might try to observe from earth.
Someone who says they do not believe in black holes either
1) does not believe Einstein's equations, of which they are solutions.
2) believes that other physical laws prevent the occurrence of these solutions.
The first paper on this Bose-Einstein condensate stuff poses another solution of the GR equations in which the point singularity is replaced with a different structure, the BEC. The math seemed all on the up and up.
(BTW the Schwartzchild solution doesn't really have a singularity. The singularity is an artifact of the coordinate system used, just like the singularity of latitude and longitude of the earth -- and we do believe in the north and south poles here, right? Kruskal exhibited coordinate systems in which there is no singularity.)
So what we have is a new analytic solution to the GR equations (and there are not many, so this will undoubtedly make it into graduate texts in the next decade).
The bad news is that the geometry around a gravastar is identicle to that around a blackhole. It is just different when close to the phenomenon, so all that business about terrible cosmic death at the hands of a gravitational giant is still there.
Yes. But they drop like a rock and leave a terrible pit in your stomach. Oh, that empty feeling!
Of course, neutron stars kill you just as dead and almost as flat...
Miko O'Sullivan
Is this the same Bose of "wave radio" fame? Pardon my ignorance about even rudimentary scientific concepts and ideas.
....I never actually sat down and thought about it, but as I was reading this article, a thought occured to me (and I'm no physicist, so don't hold it against me!). If a black hole has infinite energy and pressure, wouldn't it expand? And if it expanded, and nothing could escape it, wouldn't it begin "swallowing" the universe? Furthermore, this would mean that the existence of a black hole would "collapse" the envire universe. I don't know how long this would take (if it WERE true), but I'm sure we would have heard about it... Just a thought. Feel free to comment.
Couldn't miss him, had gas swirling around him so fast you'd think he was a star. I said to him in the sultriest voice I could muster, "hey daddy, wanna show a girl what's past the event horizon?" I ran my hand suggestively through a hydrogen cloud twirling lazily around him. (Little could he have suspected the scoop I was after. One glimpse at the singularity and my dissertation would have written itself. But I was in for more than I bargained for.)
"Sure" he said coolly. "Poke your head right in. Just don't stay too long, I have other business"
I approached the horizon tentatively, shoving my way past the gas and avoiding the chunks of rock careening around. One nearly took my head off, and I was dodging left and right, with just one thought, to get past it all and see the singularity. As I was about to duck my head past the event horizon I heard a far-off voice say, I could tell you, but then I'd have to kill you. In horror, I realized what I was doing, changed direction and with all my strength pushed away from that magic line. I whipped out my calculator and entered a thirty-line equation. Two, three seconds later I had my answer.
"Hey, it's no skin off my back", the black hole said lightly, and moved off.
The blood rose in me furiously. I opened my mouth and screamed "Bastard" so loud my eyes hurt, then tried to spit at what had very nearly cost me my life -- and job. I started shaking, a few tears rolled down my eyes, and soon I was sobbing.
"It's okay", my partner said. Thank god you're here, I answered and let him hold me until I stopped trembling.
"You couldn't have known", I heard him say, from far away, but I was already starting to pass out. You couldn't have known.
in any rogue's gallery of astronomical evildoers, black holes would have to be the No. 1 nightmare
Space-time isn't just an abstraction: It's as real as, say, toffee, and, like toffee, can be twisted to form the gravitational "wells" into which masses fall
I gotta get me some of that toffee....
This story first hit /. several weeks ago. I am glad to see the astrophysics community taking it onward and upward. Me no like blackie-holes. There is that ugly problem of infinities, entropy imbalances, loss of information, and so forth - none of which appear in the gravastar model...with the added bonus that a gravastar in every other way behaves exactly like a "black hole" (gravitationally).
Cosmology DOES contain ideas of phase changes occurring during the development of the universe after the big bang, so gravastars with space-time phase changes fits in there too.
It still permits sci-fi some cool material too, so the loss of classic black holes would be no biggie on that front.
Bring REASON back and eliminate "black holes". Silly, impossible buggers they are.
In Bushworld, they struggle to keep church and state separate in Iraq as they increasingly merge the two in America.
They don't seem to have improved their results since the last time this appeared on Slashdot. The main problem: "gravastars" require a rather bizarre stress-energy distribution. There is no reason to believe that a collapsing star takes on a configuration even remotely similar to this.
in current cosmology and astrophysics. For instance, the recently observed accelerating expansion of the universe suggests there is a small positive cosmological constant, i.e., in effect a repulsive grvitational force alongside the attractive gravitational force we all know and love. This make redshift data arguably subject to re-interpretation, for instance. Black holes were first predicted by Laplace in around 1790 (!), using only Newtonian gravity. Einstein's theory of relativity (compatable with Newtonian gravity in the appropriate limits) includes black hole solutions, as any student of Laplace would expect it to. The black hole solutions contain a mathematical singularity-a sure sign of the failure of a physical theory. Hence the effort to find explanations for what goes on during black hole formation. It must also be noted that there is fairly definitive evidence for the existence of something an awfully lot like a black hole existing in a lot of galaxies (including our own).
I read an article (can't even remember if it was electronic or paper, whuch less where it was) on this same subject a month or so ago. In it, I recall that the 'repulsive force' inside the 'black shell' was said to be akin to the expansion of the universe like a giant set of Russian nesting dools.
Bose-Einstein condensates? Einstein made speakers?
13 year old white supremacists are shitty web designers.
Oh, right, something sensible, then.
dinner: it's what's for beer
This "Gravastar" might be indistinguishable from a black hole. The article says that the star collapses to the point that the material undergoes some kind of phase transition to become a single waveform of space-time, analogous to a Bose-Einstein Condensate.
If this happens when the object is less than a Schwarzschild radius in size, it would look and behave exactly like a black hole to an outside observer.
(The Schwarzschild radius is the distance inside of which not even light can escape from the object. It doesn't make a difference how the matter is distributed inside the Schwarzschild radius)
I'd also be interested to know how gravastars scale with mass. The article mentioned only stellar-mass black holes, but our greatest evidence for BHs is the supermassive black holes that are thought to exist at the centers of most massive galaxies. These have masses of millions of solar masses; can a gravastar hold up that much mass?
Liberal (adj.): Free from bigotry; open to progress; tolerant of others.
Could you please explain us this evidence ?
I don't see any evidence. We only know that current phisic theories predicts the existense of black holes. But we can not create a tiny blackhole in laboratories. And we never saw a blackhole. The photographs we have from HST (like this one), only shows a huge concentration of matter. This is not necessary a black hole.
To believe in the existense of black holes is like to believe in god. Only faith (in current theories) can make us believe in them.
I personally think this proposal of the existense of a "gravastar" substance, is as weird as black holes. But it's normal to create "patch" theories when the main theory has problems. This will happen until we have enough data for a new Einstein to discover a completely new universal theory.
MOD THE CHILD UP!
This discusses the possibility of tiny black holes created by high-energy collisions (discussed in a previous Slashdot), which the researches hypothesize happens regularly in our upper atmosphere (bit of a stretch). It also discusses a novel theory as to why gravity is so significantly weaker than other local forces -- That unlike other forces, gravity acts through all the 'extra' dimensions hypothesized in super-string theory.
One of the more interesting things about the article is that it shows that with recent developments (the new Large Hadron Collider, etc.) scientists are beginning to reach a point where they can start to prove or disprove parts of super-string theory... Interesting stuff indeed!
A black hole would swallow clouds of stars like a whale gulping down plankton. Black holes would literally be points of no return; fall into one, and you'd be trapped forever. If Earth bumped into a black hole, it would be goodbye Earth.
This part right here tells me the author doesn't know much about Black Holes! First of all, they are not that big. In fact the largest, and abnormally, sized Black Hole that we can observe is about 14 magnitudes greater than our own Sun. Add to that the actual size even then is perhaps the size of the moon, or less!
So when a black hole travels though space-time, it gets near another object, the process that starts takes years to finish. IT does not gobble up handful's of stars at one sitting.
We can detect Black Holes by observing the siphoning of the starts gas from a long distance. It looks like the star grows a very thin and long tendril that extends away from the star main sphere. The tendril of star stuff isn't directly consumed by the black hole. The Tendril actually forms a swirl of gas around the black hole. As the black hole closer to the star, the tendril changes form to a more amorphous shape. At that point the black hole would be totally shielded behind a torrent of star-stuff that would totally block it out any direct observation. The Star, and the black hole would begin to revolve around one-another in a dance that would end with the black hole assuming the mass of the star.
If you can imagine what I just wrote, that is what astronomers have observed.
Not only that, the author also appears to have a gross inability to describe the Bose-Einstein Condensate. The reality is that a condensate cloud could probably never exist in nature, and to call it the actual space-time stuff is absurd. The condensate cloud is more like the 5th state of matter (solid, liquid, gas, plasma, and Condensate cloud). Think of a Condensate cloud as the extreme opposite of plasma. Where one is really hot, the other only exist at supper cold temperatures. In fact, the Bose-Einstein cloud is the coldest thing we have ever created I think. At such a cold state of matter, time almost seems to stop. A really bizarre occurrence is when photons are shot into the cloud, and they appear to slow down while in the cloud, then speed up as they exit.
This same topic was publicly introduced in the Scientific American magazine a few months ago. The article was interesting, but at the end had this part about how the universe could actually be surrounded by a giant condensate cloud. The idea sounded really good until that part.
What this seems like to me is we humans have recently discovered this cosmic snaik-oil, the cold condensate cloud, and are now looking for a place to make it fit in the universe, no matter how sensational.
It isn't a lie if you belive it.
Well Captain, it looks like a distortion in subspace!
"We live in our minds, and existance is the attempt to bring that life into physical reality" Ayn Rand
Let me see... oh yeah...
Heretic! Blashphemer! [sp?]
Whatever turns their cranks. Personally I don't believe most of what comes from theoretical physicists. I think they make up this shit that is hard to prove for the sole reason of making jobs. Sure lots of its practical but alot is not and in the mean time we still have practical things to work out of society like money, hunger and religion.
Why not concentrate such powerful minds on coming up with solutions to problems that will make the world a better place. In the shortterm who gives a rats ass if there are blackwholes a million billion miles away. That doesn't cloth or educate [see what tuition is for a first year in college] the not so well off portions of society and I am not even talking about the homeless!
If these people were so smart they wouldn't turn their backs on the majority of society. Instead they are fame hungry self-centered little bitches trying to get their faces on SciAm and aim for Tenure.
Whatever...
Tom
Someday, I'll have a real sig.
nuff said
As best as I can judge (not well), both theories explain the same evidence, and neither seems particularlly simpler than the other. So there isn't yet any reason to choose between them, except that people like to decide quickly, so as to simplify their world model.
... at least until we got a good look at a real one.
There are tests that are possible, so it's predicting a real difference. Unfortunately, I don't know of any that are exactly practical for us to undertake (could be wrong here, I haven't been paying that much attention).
This isn't unusual. It is frequent that there are multiple theories that explain what we know equally well. Usually the simplest one is the one that people stick with, but the first one to appear has a big edge. So black holes will probably win out until we get close enough to really examine one of the monsters. Then we may rethink things.
Still, if the brane theory and it's Big Bash wins out over the Big Bang, then there won't be any need for a singularity at the start of the universe (though I believe that Hawking questioned that anyway) so it might be simpler to just beleive that there aren't any singularities, in which case the gravstar theory would win
Truth can't ever be known, only approximated. But with skill the approximations can get pretty close.
I think we've pushed this "anyone can grow up to be president" thing too far.
They obviously haven't examined the employee suggestion box here at work...;)
"It seems that there's a growing movement that doubts the existence of black holes..."
Made up of scientists who have forgetten the principal of Occam's Razor...
You know, I've read through all of these comments (well, alot at a level of +2), and one thing has struck me....
./ subscripions won't work.
... I mean, something must have struck me, as my brain hurts. I mean really hurts. I don't like thinking about anything I've read, as waves of nausea wash over me.
Now, why would I want to pay for something which causes me pain?!? This is why
Would someone like to explain, in layman's terms, the unification of all of the string theories, and there being 11 dimensions, and how relates to this?
And could someone please explain if and how Einstien got it wrong with his general theory.
Small words only, please.
"The best part? I became an ordained minister while not wearing pants." -- CleverNickName
The folks at Los Alamos (Mottola et al.) who dreamt this up were trying to devise a scheme in which gravitational collapse led to an object similar to, but without what some perceive to be the inconsistencies of, a Black Hole. While they get points for trying, there are a lot of problems with their proposed model.
First, it requires that under extreme situations gravity undergoes a "phase change", which for all intents and purposes means that the region inside the gravastar posseses a positive cosmological constant, effectively a non-zero energy density inherent to space itself. The notion of a cosmological constant has been troubling relativists and particle theorists for over 70 years and we still don't understand whether there is such a thing and where it might come from. Current astronomical observations suggest that there may in fact be a very small CC, but no one knows a mechanism for how this might be "produced" inside a gravastar. The earlier work of the Los Alamos crew makes some suggestions for how this might come about, but is itself based on a field theoretic treatment of gravity, a pretty shaky proposal whose predictions are hard to identify and must be taken with a grain of salt.
Second, they propose an interface layer between their "gravitational BEC" and the world outside the gravastar, made up of "ultra-stiff fluid". In GR we often resort to desribing distributions of gravitating energy and matter as a perfect fluid with an equation of state that relates how much energy density there is to how hard it pushes out, or its pressure. There is a "stiffest possible" equation of state consistent with causality (the speed of sound of disturbances in the fluid is equal to the speed of light). This is what they use to make their interface. Such a fluid has fascinating properties and is the subject of a lot of attention right now, but no one really knows of any such substance or what its microscopic physics might be. Therefore a lot of guesswork goes into any numerical estimates they might suggest.
Third, their gravastars are extremely cold and don't seem as if they would be useful for the types of processes that astrophysicists typically invoke Black Holes to explain. Black Holes are conjectured to be responsible for a wide array of highly energetic processes that we see in the Universe, and these gravastars just don't seem as if they would even be stable in such situations.
Last, if you go to http://arXiv.org and search for this paper, you will see that it has been revised five times since it was originally submitted. It isn't unusual for papers to be revised, even that many times, but I know that some of the revisions are due to calculational errors.
The paper is entertaining and has some neat ideas, but is in all likelihood not the way things are. There is a movement among some condensed matter physicists who claim that the principles of CM physics are actually fundamental and should form the basis for any consistent model of gravity and particle physics. This paper is a nod in that direction. While some ideas from CM might find fruitful application in high energy physics, it doesn't seem likely that phenomena at the Planck scale (where quantum gravitational effects become important) will benefit from them.
I think this is just another case of building "spheres within spheres" to make a model that allows a non-fuctional theory work. You can't explain away black holes and other strangeness in Einstien's work. Like what has happened with quantum physics, many less imaginative scientists saught ways to explain or disprove the "weirdness" of quantum physics...similarly, they are *still* looking for ways to explain away the weirdness in Einstien's work. Quantum Physics works, and so do the Special and General theories of Relativity. Just because they give you some results you don't like doesn't mean that they are wrong.
Remember, the Universe is not only stranger than we image, it is stranger than we *can imagine*!
ttyl
Farrell
CAN-CON 2019 - Ottawa's only book oriented Science Fiction Convention! October 18-20, Sheraton Hotel, Ottawa, Canada h
"Gravastars"? I thought we had decided to call them "Doomspheres"!
Read this, its amusing.
...
Hi there,
so if i read the slashdot article right, then a black hole is:
-a high-energy bose-einstein condensate composed of whatever 8013200000000000000000000000000 metric tonnes of neutronium compresses into, surrounded by van allen belts made of stellar quantities of fusion-host plasma orbiting just below where above-light-speed gravity pulls it and just above where space curvature makes it's trajectory a straight line.
Hmmm...
Oh, and the whole assemblage is at best on the ragged edges or at worst in another universe entirely (the event horizon being a stable stellar-scale quantum tunnel) because time is moving backwards, stuff is moving faster than light, and the condensate isn't just a condensate, its an (exploded neutronium fireball/phase-shifted matter agglomerate) inside a space warp where the curvature a) makes the space it occupies orders of magnitude larger on the inside than the outside; b) is so curved you cant see the whole thing from any one point even on the inside; and c) the gravity right to the inner band of plasma is so strong it shears electrons out of nuclear orbit.
Ok, i think i got it.
(Yeah i know it's not quite worded right, but you get the idea)
I read a really good article last month online from MIT that theorized that x-rays and other types of specific waveform radiation do not cross the event horiziong, but rather are 'more' attracted by the gravitational pull and actually accellerate to FTL speed in the form of pure energy... they are drawn in, but bounce at the 'core' or energy conversion point as their waveform does not blend/match the conversion point inside the black whole, thus reversing direction... as they exit the energy bleeds and the rays re-shift to sub FTL speeds and matter form.
A brilliant philosophy professor of mine once described the formulation of fantastic theories unsupported by enough empirical evidence as "creating castles in the sky". Black holes, we may one day find, are far more tangible, real, and even observable than a puff of clouds that resembles a drawbridge. When confronted with phenomena that cannot be explained, a select few physicists and astronomers are apparently compelled to come up with the most unlikely explanations, seemingly borrowed from bad sci-fi movies. Witness the dark matter debacle, in which the many interesting (read: ridiculous) theories concerning other universes and dimensions suddenly caved to the harsh fact that dark matter really *is* nothing more than matter that we can't observe for a myriad of reasons, and not matter sitting in some kind of other space-time continuum. Occum's razor, baby--Occum's razor.
Theory 1: Everthing you observe is because I want you to observe that way. You cannot figure anything beyond because you neither have perception beyond that nor you can figure out what I like and in which ways I make you see things different than they actually are. You see, you also observe a "me" which is substantially different from real me. I can't tell you what reality is, it would be no fun. Even this post is partially true but it is as close to reality as you can/will ever manage; I'll see to that.
Theory 2: Whatever I say is internally consistent because I say so. Everthing is either something I would say, or not consistent with reality. You might think othewise time to time but you are obviously mistaken when you do that.
Gentlemen, you can't fight in here, this is the War Room!
OK, let's start with what we know. From the article: "Astronomers are sold on black holes." Yes, they are. Black holes are out there. The question is what's inside.
Nobody can see inside, so it's anybody's calculated guess. The two main problems with the current theory are singularities and entropy.
Personally, I'm not a huge fan of singularities. I think it's a cop-out to say, "at some point, all the known laws of space-time break down, and that's that." Many people seem to be of the same mindset, including the authors of this paper. They suggest that at some point, the collapse of the black hole is balanced by some quantum force. Now, if I recall correctly, didn't Hawking already suggest this himself?
As for entropy, Hawking wrote that black holes emit radiation by sucking up nearby anti-particles. I've never understood why black holes should statistically acquire more anti-particles than particles, but then again, nobody understands the statistical nature of matter vs. antimatter anyway. I'll take his word that the math works.
This paper amounts to little more than a comparison between black holes and Condensate, and considering that condensate is near-absolute COLD and black holes are something akin to absolute HOT, I think it's a pretty immature analogy.
The paper isn't even published. Why are we talking about it?
Would that be rather like neutron stars? My understanding is that current orthodox astrophysics models meutron stars as either a Bose-Einstein state, or as (in effect) a single, very big, neutron. (Or, er, are those the same things?) C'mon astrophysicists, enquiring idiots want to know! ;)
:).
Neutrons are fermions, as another poster pointed out, so they don't form a Bose-Einstein condensate.
Instead, they form a Fermi-degenerate system. No two neutrons can have the same quantum state, so they "stack up" from the lowest energy state on upwards (just as electrons "stack" to fill the different orbitals and shells in an atom).
A neutron star doesn't have many protons. Electrostatic repulsion between protons packed that densely would cause them to have a horrifically high potential energy, so instead they merge with electrons (at an energy cost) to become neutrons (or you could consider them to emit positrons; same net effect, different reaction path).
For the electrons bound to an atom, electrostatic forces are what cause the electrons to stay bound. For an atomic nucleus, the Strong force keeps the nucleons bound. For a neutron star, gravity keeps them bound. But you end up with the same kind of system in each case - particles that exclude each other filling up increasingly-energetic orbits because they're not allowed to have the same state.
A neutron star could be thought of as being similar to a giant _nucleus_, but it'll have many interesting features not found in an atomic nucleus (because it's big enough that the Strong force only affects parts that are really close to each other, and because you can get more ordinary material piling up on its surface, and because very high energy orbits many make other kinds of decay energetically favourable).
I hope this helps
You misspelled Mr. Occam's name. See here for nice writeup of Occam's Razor.
Hawking and...I think it was Penrose were studing singularity for Hawkings PhD. They used the mathematical calculations for sungularity in black hole and reversed the "time" aspect of it all to find out if calculations were in check with the "space" aspect, since time and space are intertwined into the fabric of "spacetime". When they completed their analysis they realized that all this supercondenced matter could be emitted the same way (reversed) that is was created. They thusly proved that this big bang theory is true. Now, of you believe that the big bang theory is true, mathematically, you must also believe in singularity and black holes. (Since blackholes are only a singularity that warps spacetime creating an event horizon). Even that cathloc church in 1951 ratified that the black hole theory was true. They don believe in anything!!! Please post any additional comments.
I once shot a man who posted too many, "Imagine a beowulf cluster of these"
I understand gravastars taste terrific with cream cheese and red onion.
Ok, this has got to be about the dumbest comment I've seen tacked on the end of a story.
-
- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
the article says
They may be destined to go the way of other scientific Dodo birds like the "celestial spheres" of medieval cosmology and the vaporous, cosmos- pervading "aether" of Victorian astrophysics.
that's funny, the writer picked two theories that haven't quite gone away.
celestial navigators (ship and aircraft) use a copernican model of the heavens. yes the earth is the center of the universe and yes all the stars are on the enclosing sphere.
and the aether theory is making a comeback in some circles too.
...except in astrophysics:
Q. We estimate that the Andromeda Galaxy is 2.2 million light years away: does this contradict the creationist notion of a young (~6000-year-old) universe?
A. Either you are wrong (shifting Hubble constant) or God made the universe that way (i.e, the light from Andromeda was created en route).
...except in nuclear physics:
Q. How can there be rocks on earth which we estimate are 3 billion years old through radiative half-lives?
A. Either you are wrong (varying rates of decay over time) or God made the rocks that way (crystals with small amounts of uranium and lead and other fission by-products which just happen to match a 3 billion year ratio).
...except in lot of other places. Most of science is a mutually supporting web of facts and theories and hypotheses (NOT the same things!). To claim that ONLY certain parts are wrong (e.g. evolution) usually has ramifications in other sciences.
Disclaimer: Math is a powerful tool, useful so long as you don't grant it primacy.
The fundamental point of the theory of relativity is that observations are relative to the observer.
An observer who is at rest or close to it will see, through relativistic time dilation, all the matter (and energy, charge, angular monentum, entropy, extropy, whatever) that has fallen towards a black hole piled up asymptotically at the event horizon.
To an observer riding along with that matter it will look very different. There will be no actual bump to indicate the event horizon, especially for a big enough black hole where gradient effects don't become problematic.
On the other side of the event horizon, the observer's flashlight beam will, at least if shone in certain directions, circle back to him. However he might still see red shifted light from the outside world that has entered the black hole with him
I suspect things get even more interesting from the frame of reference of an observer approaching near the event horizon at a velocity which will evade capture, but as far as I know the math has only been attempted for the simplest of those situations.
Given that observed gravitational curvature of space required that the substance of "empty" space form an extensive 3D manifold in some extensive 4(+)D coordinate space, the crowding in 3D coordinates might be at least partially compensated by stretching in the extra dimension(s) and thus provide an escape clause for the observer from ever actually encountering the total disruption that a singularity is presumed to imply.
While we might be attracted to such an escape clause, it would seem hard to reconcile with Lee Smolin's ideas about the evolution of physical laws over many generations of proto black holes and big bangs.
-- Our systemic servants do not good masters make.
I know someone already said this, but photons HAVE NO MASS. NONE. The concept of linking mass with momentum comes from Newtonian mechanics, and does not always apply! As far back as the 1600's (Galileo), we figured out that gravitational acceleration was independent of mass. If we take the limit of this as mass goes to zero, we see that even something that is massless will be accelerated in a gravitational field. Think of it this way - we know (from relativity) that the percieved mass of an object increases as we see it speed up, to the point where it is infinitely massive at v=c=speed of light. If a photon had mass, the fact that it is moving at the speed of light implies that it would have infinite mass and therefore infinite energy. Of course this is unphysical, so light cannot be massive. That's just one explanation that is very thin on details and is overlooking a few things, but you get the idea.
joerobe
The best way to predict the future is to invent it.
Proving that a theory is consistent with observable phenomena and proving that it is true are two very different things. That is the first thing they teach you in every intro-level science class. Yes, the big bang theory, and the black hole theory are consistent with observable phenomena provided that you assume certain premises. This is a long way from proving them to be scientific fact, though, and some people will dispute the premises.
As for what the Catholic Church has ratified as true, it most certainly not does not include any such thing. The Church does not declare dogma on such matters. In point of fact, only three dogmas have been prolaimed in the last two centuries: the Immaculate Conception of the Virgin Mary (not to be confused with the Virgin Birth of Jesus), Papal Infalibility (in matters of faith and morals), and the dogma of the Assumption of the Blessed Virgin Mary. What the Church does with scientific theories of this sort, is simply to declare whether they are consistent with the faith (i.e., whether Christians can believe in these theories and remain faithful Christians). This is what Pope John Paul did with evolution (with some caveats) a few years back. Beisides, only doctrines that carry near-universal belief within the Church, and are: 1) consistent with Scripture and 2) consistent with the nearly two-thousand years of Sacred Tradition of the Church can be promulgated as dogma in this way - we don't declare new dogma, just that old ideas are finally decided to be definitely true.
To say that Catholics don't believe in anything isn't true at all (trust me, we believe in a lot, most notably Christ), but the Church's mission is to determine truth in matters of theology, not matters of science. As a practicing Catholic who has yet to make up his mind on such issues as black holes (for lack of scientific proof and because I haven't done the last of the research I would need to do on the subject to form an informed opinion, not because of any matter of faith) I can tell you with absolute certainty, that the pope has never said any such thing as "black holes are a fact."
Frankly, it seems odd that every time we have one of these debates, the argument "even the Catholics believe that!" pops up. Who cares? If you are not Catholic then what weight do our beliefs carry? Are you attepting an argument of truth based on lack of counter-example? You can't win with such an argument, since if there were no counter-example, then there would be no debate. The debate itself is the counter-example. Why bring religion into a rational scientific debate? At least be accurate if you do.
Sorry if this comes off as a flame. It is not intended as such, only as a rational, if passionate, rebuttal. I didn't even mention your lack of citations (well, now I did, but not in an angry way).
I made a Bose condensate in my own bedroom, it's not that hard to do. I was translating the spacial coordinates of the masses in the room relative to the window (rearranging my furniture) and put my Bose Lifestyle speakers and Bose Waveradio on my bed.
When it came time to move that, I picked the blanket up first, carefully, by the corners, and the speakers and Waveradio all tumbled to the center of the blanket, condensing down to a very high density of high-fidelity sound.
I don't know about a condensate of both Bose equipment and Einstein equipment (in fact I've never heard of that brand... anyone have any of those at home? Are they as good as Bose?) but it couldn't be much harder to make than the Bose condensate.
~Me.
The neutrons then pack together more and more tightly until the repulsive force between the neutrons prevents further collapse (for stars not quite massive enough to become black holes)
Which force causes neutrons to mutually repel one another?
That that is is that that that that is not is not.
Yeah, who are you? I thought I was stating my view on the posted topic based on the information provided, as well as other information I gleaned from a search. I didn't realize that I was "wrong", though. Thanks for setting me straight on that, citizen!
:)
What's weird is that I just took an introductory astronomy class (oh yes, I'm *just* that ignorant) led by one of the most prominent physicists on the East coast. This same man would undoubtedly take you to task on your "flat universe" assertion. I promise. To be honest, I'd rather place my faith in his intellect and knowledge over yours. You are, after all, a completely unaccredited, more or less anonymous slashdot poster. I admit to not having a doctorate in physics, can you?
I don't need a new dribble glass when you spout off jargon such as "cosmological constant" and "baryonic"--I'm familiar with the terms. But maybe you could impress my professor with how much you know? I can give you his email if you'd like.
The fact is, dark matter/energy ideas are *all* conjecture based on conflicting, irritatingly persistent facts that cannot be consolidated under any one bizarre, all-inclusive theory. That was the point of my post. So as they say, don't pee on my head and tell me it's raining.
Good day
Snotty bragging about your classwork aside, the other poster's statements are correct based on the latest accepted estimates. See for instance, this FAQ.
Look at this figure; a flat universe falls neatly right in between the error bounds.
my mistake !
by mass I ment the energy part of the energy-momentum 4 vector P_0
this in massive objects looks like m(v) = m_0 +
and it is != 0 for photons.
but of course the definition is the eigenvalue of P^\mu * P_\mu operator, which is zero for photons.
dunking meself at sink
Working for necessity's mother.
Just thought I would share this with you guys. I went into this movie thinking it was a horror flick (which I love) but I was pleasantly suprised, it was about black holes and time travel! Great movie, informative, funny, and it makes you think! It's called Donnie Darko, an independent movie from the Independent Film Channel. It was in theatres though and I believe is now on DVD. It presents one small instance in time travel/black holes and lets you do with it as you wish! You can think whatever you want, it doesn't limit you. Check out the website too, it's great hypertext site! donniedarko.com. Have fun!