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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
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
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
"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
First Corollary to Skirwan's First Law of Creationism: Skirwan's First Law of Creationism provides direct support for creationism.
Second Corollary to Skirwan's First Law of Creationism: Evidence designed to contradict Skirwan's First Law of Creationism does not exist. The nonexistence of such evidence provides direct support for creationism.
In related news:
--
Damn the Emperor!
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.
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.
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.
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
And creationism *is* internally coherent? Bahahaha!
-- Give me ambiguity or give me something else!
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?
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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 =(
" 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
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.
I have serious concerns against that theory.
What doubts do you have? That's one of the central results of Special Relativity, and so far we have failed to disprove it. It is also used to predict the energy yield of nuclear reactions, where m is the "mass defect" - the difference in mass between the reactant(s) and the product(s).
Einstein had a hard time convincing people because relativity was so radically different from Newtonian mechanics. In fact, it was because of this that he did not receive the Nobel Prize for relativity - he got it for his work on the photo-electric effect. Relativity was simply too radical a departure from the accepted state of Physics.
Cheers,
Tim
It's official. Most of you are morons.
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.
Of course, neutron stars kill you just as dead and almost as flat...
Miko O'Sullivan
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.
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.
Time travel is still entirely possible; you don't need a singularity for that. If nothing else, build a Tipler Cylinder. It just has to be really really dense (neutron star material will work) and spin really really fast (to be precise, such that the surface is moving over half the speed of light) and be really really long (technically infinite, but close to the middle of a finite cylinder should work; you'd need miles of the stuff to send a human back, but sending a gamma-ray communication laser could be a million times smaller).
PHEM - party like it's 1997-2003!
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.
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.
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...;)
cool. I remember it well.
"RUN, COWARD! HAHAHAHAHAH"
You had to "mine" stars by shooting them to collect bits of smart missiles to smack sinistar with and the movement model was like "Thrust".
I think the original is in a Williams arcade pack for the pc they made ages ago: you also got defender, some defender sequal and a lamo bonus game where you walked round as an insect/teapot/some J Random Surreal thing and avoided stuff and collected other stuff.
And yes, I've been up for 25 hours, can't type and have 50 karma, so I don't care.
graspee
Well, that wouldn't really be counteracting gravity. No more than putting something in a box is countering gravity. You're manipulating the environment (in this case, space time) so it keeps whatever where you want it.
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
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.
Damn the Emperor!
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
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.
Its actually quite easy, considering that the traditional Judeo-Christian definition of God, and for that matter any definition of God that includes the concept of being supernatural, is self-contradictory.