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Black Holes Not Black After All, Theorize Physicists
KentuckyFC (1144503) writes Black holes are singularities in spacetime formed by stars that have collapsed at the end of their lives. But while black holes are one of the best known ideas in cosmology, physicists have never been entirely comfortable with the idea that regions of the universe can become infinitely dense. Indeed, they only accept this because they can't think of any reason why it shouldn't happen. But in the last few months, just such a reason has emerged as a result of intense debate about one of cosmology's greatest problems — the information paradox. This is the fundamental tenet in quantum mechanics that all the information about a system is encoded in its wave function and this always evolves in a way that conserves information. The paradox arises when this system falls into a black hole causing the information to devolve into a single state. So information must be lost.
Earlier this year, Stephen Hawking proposed a solution. His idea is that gravitational collapse can never continue beyond the so-called event horizon of a black hole beyond which information is lost. Gravitational collapse would approach the boundary but never go beyond it. That solves the information paradox but raises another question instead: if not a black hole, then what? Now one physicist has worked out the answer. His conclusion is that the collapsed star should end up about twice the radius of a conventional black hole but would not be dense enough to trap light forever and therefore would not be black. Indeed, to all intents and purposes, it would look like a large neutron star.
Earlier this year, Stephen Hawking proposed a solution. His idea is that gravitational collapse can never continue beyond the so-called event horizon of a black hole beyond which information is lost. Gravitational collapse would approach the boundary but never go beyond it. That solves the information paradox but raises another question instead: if not a black hole, then what? Now one physicist has worked out the answer. His conclusion is that the collapsed star should end up about twice the radius of a conventional black hole but would not be dense enough to trap light forever and therefore would not be black. Indeed, to all intents and purposes, it would look like a large neutron star.
....huh?
Or just not quite as dense as we thought.
You're looking for quotes? See my journal.
Frozen Star by George Greenstein had as a central theme that due to gravitational time dilation that we could never see a star collapse beyond its own event horizon: it would asymptotically approach it as arbitrarily close as we liked given unlimited time but never cross it. So as a natural consequence there was always a tiny but measurable probability that trapped light and thus information could escape.
Although this is a layperson's work, it is based on his published papers which provide a mathematical background.
-- Insert witty one-liner here. --
physicists have never been entirely comfortable with the idea that regions of the universe can become infinitely density
I'm pretty sure that editors outside of /. have never been entirely comfortable with that idea either.
Ezekiel 23:20
Orange is the new black...hole...
"He's lost in a 'floyd hole"
physicists have never been entirely comfortable with the idea that regions of the universe can become infinitely density.
Infinitely density. Wow. The Engrish need helped.
I know that Black Holes aren't supposed to be observable - but I thought there were observations of other things, such as things being eaten by black holes and the interactions between a black hole's massive gravity well and the environment around it. If this study is right, shouldn't the astrophysicists who first observed the by-products of black holes have been able to see them?
following the convention for naming stars that are not dense enough to ignite "brown dwarfs", we could name these new, less dense, singularities... "brown holes".
Now how is Michio Kaku going to portray black holes as marauding monsters that travel around like itinerant serial killers, gobbling up everything in their path?
WTF does a large neutron star look like then?
Lost at C:>. Found at C.
physicists have never been entirely comfortable with the idea that regions of the universe can become infinitely density.
They've clearly never been to DC. I'm convinced that regions of the universe are infinitely dense.
Slow down, cowboy! It has been 4 hours since you last posted. You must wait another few hours.
What's with the Really Old News?
... "I am the Doctor" by Murray Gold as if some absurdly clever Man has just saved a planet. Anyone Else? Just Me? *sigh* Fine.
Or... maybe it doesn't devolve into a single state at all. We can't actually see what goes on inside of black hole... but if our assumptions about what actually happens appear to create a paradox, then maybe it's our assumptions aren't valid, rather than the original basic concept of what a black hole supposedly is. I believe that the concept that black holes are necessarily singularities may be flawed. Space is so distorted by gravity in their vicinity that straight lines which intersect their event horizon never exit it, but I do not think that means that all of a black hole's mass is necessarily at its center, or even necessarily collapsing inexorably towards its center. Its center is just its center of mass.
And yeah, I know that astrophysicists with a vastly more qualifications than I have came up with these ideas, but in the end, an argument from authority does not make one actually right.
File under 'M' for 'Manic ranting'
can some explain why information can't be lost? this is slightly confusing and that assumption makes it seem like they're building a lot of theory on a pretty shaky foundation.
that would be racist.
My karma is not a Chameleon.
We're going to keep calling Pluto a planet.
We're still going to call Black Holes Black Holes.
Seriously Dark Gray Holes just doesn't have the same ring to it.
What you say! These is much English goodly!
IIRC, string theorists have also proposed the idea that there are no singularities. In their model, the gravitational collapse of a star of sufficient mass causes all the strings of its component particles to coalesce into one highly-energetic string, sort of a super-particle. The information content of the original matter would be preserved in the vibration pattern of the final string.
Koans and fables for the software engineer
No, you are dead wrong, completely and utterly wrong. "For all intents and purposes" has been down-grammaticised into "for all intensive purposes". The latter has no actual meaning.
char*f="char*f=%c%s%c;main(){printf(f,34,f,34);}";main(){printf(f,34,f,34);}
Why does it have to be a collapsed star? To a casual observer it appears no different then a drain of some sort. Where it is draining would be my question.
And most of the posts on this story are worthless jokes or statements meant to make light of stupidity and convey it as a virtue.
Thanks for adding your own worthless post...you must be a wizard! Feel free to come back any time. (anytime you're not hanging out on that circle-jerk known as reddit, that is)
"For all intents and purposes" is the correct statement. "Intensive purposes" isn't a thing, unless you mean that any laid-back purposes are excluded.
On the other hand, if you're being sarcastic, why not go whole hog with "intensive porpoises".
Why not just admit that then?
"For all intents and purposes" has been down-grammaticised into "for all intensive purposes". The latter has no actual meaning.
That is untrue! For all intensive purposes i use an exercise machine!
This Space Intentionally Left Blank
If visible at all. Interestingly, purple is literally made up in the human mind. Your eyes cannot process it, your mind does!!
Humans don't really see purple. They sense it through their mind.
Time-dilation is infinite when you hit a black hole. That means it takes infinity time for an atom to pass through the event horizon. Therefore nothing EVER can, and goop just builds up outside. That's another way to look at this result.
They do devolve into a singularity.
This creates the 'black hole' in our universe, something that can be accurately described as just one system with very few descriptors.
The 'lost' information/matter/energy is what causes a 'big bang' for a new universe created when the star collapses into a singularity.
This information, to be useful for the newly created universe, must be hidden from ours in order to 'balance the books' of entropy and information.
That is the 'self censorship' observed in our universe with the event horizon.
http://en.wikipedia.org/wiki/Cosmic_censorship_hypothesis
Our universe is just a 3d holographic projection/mass delusion housed within the singularity of another parent universe.
http://en.wikipedia.org/wiki/Holographic_principle
The serpent eating it's own tail is what is reality. Endless universes being created and consumed to create more universes in an endless cycle of destruction and birth. Time without end, creation without beginning.
You are correct, for all the taking that is done in DC, no information actually escapes. Fortunately nothing of value is lost, unless you value money, then you are hosed.
What's this about radius of a black hole? Circumference or surface area makes better sense to us, radius of an object with such intense gravity is difficult to comprehend due to the relativistic effect on distance, so comparing radii is not helpful to most of us.
It's like... how much more black can this black hole be? None.. none more black.
Could it also be that black holes are dark matter?
People are confused by basic astronomy language. There are two things in the universe, those we can see, and those we can't. The only things we can see from Terra are stars that are bright enough to be seen lightyears away. Stars are Bright, everything else is Dark. Dark Matter and Dark Energy refers to anything that's not part of a star.
For hysterical raisins of course...
Dark Energy?
Would a 'negative energy' zone potentially produce Dark Energy, which is the repulsive force accelerating inflation?
Does this explain why inflation is increasing? More 'black-hole-type' objects with more of this negative energy space in existence... creating more Dark Energy...
"My name is George McFly, and I am your density."
"Somebody has to do something. It's just incredibly pathetic it has to be us."
--- Jerry Garcia
Who says information can't be lost? Behold the "Blue Screen of Death"
The Dark Hole could be concentrated Dark Energy, hence it would be also bigger on the inside, than on the outside. It would not be infinite but just some kind of different beast living off in the vacuum energy, like a waste from the stars.
Note that the stars are not some very old cosmic objects but everything in Universe really very young, hence there isn't much waste produced yet.
The Universe haven't yet even decided if will continue to expand or it will collapse one day, of course we will never know what will be the idea in 100 years.
There's a Vaz difference in the region between the Schwarzschild radius and the radius of the star's observed dust ball?
In fact, this makes perfect sense. Consider that we *know* black holes evaporate via Hawking radiation. I haven't read the paper, but unless I miss my guess, what he's effectively suggesting is that the evaporation starts as the star collapses, and becomes stronger as it grows more dense, to the point where a balance is reached, *above* the Schwartschild Radius.
mark
>A lot of phenomena in astrophysics are ridiculous, but real.
No there are many ideas in astrophysics. We don't know if they are real.
Dark matter? Maybe or maybe not. Dark energy? Maybe or maybe not.
Hawking radiation? It is an idea, it hasn't been proven or disproven.
Speed of light limitation? Probably, but how are neutrinos that have mass going 99.9999% the speed of light? That should require almost infinite energy shouldn't it?
Big bang? A large body of evidence points to a time limit to the beginning of the universe, but cosmic background radiation is the only stronger evidence of a big bang --- yet this could have another explanation.
Cosmic inflation? Could be a non-starter for reasons we currently don't have a handle on --- case in point, it is only happening *far away*. Supernova are used as standard candles, but what if we had different looking supernova 10 billion years ago and our measurements are wrong, therefore inflation isn't happening.
Astrophysics is an emerging field, even now. There are few ways to test all the ideas.
Many of the theories of the exotic blackholes rest precariously on a shaky house of cards, because there is no convenient way to test the ideas.
Priest: "Universe from nothing, no laws of physics, sped up time"+ huge discrepancies. Creationism? No. Big Bang Theory
There is one unfortunate difference between Jackson and MLK. (well, unfortunate in the case of MLK.)
.... this all revolves around the notion that the information paradox is real. It could very well be that what they think of as "information" is nothing more than a layer (or multiple layers) above what the real "information" is. The universe has a habit of proving our ideas need more work... pretty much every time we have a technological advance.
Fascism: An authoritarian and nationalistic right-wing system of government and social organization. See also: NAZI's
So that your laterals may become infinitely dense...
"Flyin' in just a sweet place,
Never been known to fail..."
Your joke is not very funny. :/
You must be a visitor from Colonslash. That's another site, with a different posting culture. This is Slashdot, where anything is deemed "funny" by making comments that are equal parts clever and obtuse, in reference to a parent posting.
There are plusses awarded in "funny" for meta-references to the topic of posting, and the specific modes of posting, when used in the cited context.
You will have to forgive me, I began as a USENET chatbot, skipped IRC and was ported directly to slashcode.
"Flyin' in just a sweet place,
Never been known to fail..."
I should have tried harder in high school and college so I could really understand all this space stuff.
YHBT. YHL. HAND.
If it's in you sig, it's in your post.
Why is everyone so uncomfortable with the idea that something can be lost forever? How is that a problem? I'm perfectly sanguine with the idea that information can be lost or irretrievable. I'm perfectly sanguine with the idea that the universe will die of heat death. I'm also down with the idea that the Big Rip will swallow everything up in several billion years - talk about information loss... It just strikes me as fatuous and arrogant that humans think the universe has to work a certain rational, logical, way - like the universe gives a shit one way or the other.
Shoes for Industry. Shoes for the Dead.
Just as there is a velocity that cannot be surpassed, why can't there be a gravitational limit which cannot be exceeded. Infinity is just a term used to explain things we cant measure or define just yet.
It's time to come up with a new name, like "Large dark holes"
Ever since I was young and understood the concept of a black hole and it's event horizon, I wondered why we choose to mix in this completely non relevant idea that as the density approaches a point at which an event horizon could exist past the exterior of a star's surface, that something magical happens and matter suddenly can occupy the same space. Why did they have to do this? Why wouldn't a black hole just be a big star on the inside? Just because we can't see it doesn't mean that there's something magical. Nothing magical happens once you would cross an event horizon, other than the fact that you wouldn't be getting out. In an imaginary world, if you could cross the event horizon, yeah - you'd see a star, though of course your perception would be quite strange - as if you were surrounded by it. Anyway, whether they prove that these can be dense enough to keep their light or not - let's dispatch this idea of a singularity. It's silly.
Just because the information might have gone somewhere (inside a black hole) where we can't determine the information any more doesn't mean the information was lost to the universe.
It just means it was lost to us (and others on the outside of the event horizon.) It takes a pretty enormous ego (as an observer) to think that it matters to information's existence whether some particular external observer (like us) can detect the information.
So I don't get the paradox at all. The information is just inside the event horizon, isn't it? Inaccessible to us, but accessible to something else that was also inside the event horizon.
Anyone see where I'm going wrong here?
Where are we going and why are we in a handbasket?
But nice try ;^)
To be politically correct, you can't use the 'B' word.
Next they'll say that they aren't holes either 0.0.
There have been theories about Black Holes not really existing before, mostly working on the premise that there is no real collapse.
Most of these theories have been falsified and I see no compelling reason to revisit the notion merely because of the Information Paradox.
The dominant theory in Black Hole science at the moment is that information stays on the Event Horizon. Mass can pass through, information cannot. Information can then be radiated in much the same way as Hawking Radiation - and, indeed, might be carried on Hawking Radiation. This seems a perfectly reasonable idea.
I will go back to a theory I first put forward around 1983, which is that information has no mass and therefore the Einstein-Rosen bridge remains stable for it. For Black Holes, the bridge collapses in the presence of any non-zero levels of matter approaching the bridge. (For Wormholes, which probably exist because wormhole dynamics are exactly how entangled particles are entangled and therefore the mechanics don't contravene any laws of physics, the requirement is that net mass is zero or below.) Ergo, the bridge is stable for particles with zero real or effective mass. Ergo, information can be radiated through the bridge. Ergo, information is not lost. (I was very strange as a teenager.) This theory is quite probably wrong, but I would put it to Slashdotters that the theory is at least as viable as Hawking's idea and is at least based on known physics and plausible dynamics.
(Hawking is a brilliant scientist, no question about it, but he goes through theories faster than I go through tea.)
Me fail English? That is unpossible!
Black holes would then be what??? PPOB
IANAA (I Am Not An Astrophysicist) but I was under the impression that black holes have a non-zero Schwarzschild radius (and therefore volume). Together with a finite mass, how does one get infinity for density?
Yes, there are things about warped space that may give odd local answers frome a classical physics perspective. But using the term 'infinie density' seems to be an over simplification that is misleading.
Have gnu, will travel.
For all intestinal purposes, this thread makes me [sic].
Escher was the first MC and Giger invented the HR department.
P.S. Do "circles" exist? I have only encountered engineering approximations. Believing in "circles" is akin to a kind of theism, I think.
Sadly this only shows a complete misunderstanding of mathematics. By demanding absolute perfection you simply create a rule that is a self lie and a self delusion. The joke that mathematics itself isn't perfect or anything like it. In a way pi is the ultimate joke because it is the point where physics invades and corrupts mathematics irreversibly - nothing much more advanced than pi can ever be totally absolutely pure.... Real mathematics is a hodgepodge of evolution and ill fitting pieces hammered together to make them work. Just try testing general relativity with KISS - Occam's razor. It fails miserably, because its maths can't be reduced to basic axioms.
There are a dozen other ways of breaking general relativity, perhaps the simplest is that it defines a universe that cannot exist because it doesn't define a stable FTL universe. Do you know why tens of thousands of physicists over 100 years have failed to break general relativity? an aura of inscrutable mathematical perfection and completeness - that is an illusion. That kind of absolutism belongs in religion not science. Yes there are real circles.
Below the speed of light Special Relativity is one of the most accurate theories in physics - above the speed of light..
Hand me one of these.
"Flyin' in just a sweet place,
Never been known to fail..."
No, you can only use an exercise machine for some intensive purposes. There's nothing that applies to all intensive purposes, except being intensive. And purposes.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
Yeah, but i'm just talking about myself. I'm pretty lazy and don't do most of those other intensive purposes. Of the intensive stuff i do at least 90% of it is on an exercise machine.
So for all intents and purposes i use an exercise machine for all intensive purposes.
This Space Intentionally Left Blank
(1) the math doesn't break down, the theory does. If the math broke down as well, we wouldn't know the theory had broken down.
(2) an analogous discontinuity of the Earth would be "falling off the edge of the Earth", as some used to believe. That broken theory got changed centuries ago.
(3) I know of no one that thinks of subatomic particles as points but I do know of theories whose flaw comes from them being based on point particles.
Disclaimer: Mr. Thornley and I have a history
I come here for the love
Simple extrapolation of super string theory.
We want... a shrubbery!
So, would a 360 degree arc drawn with a very good sturdy compass suffice?
“He’s not deformed, he’s just drunk!”
That is an "engineering approximation" of a mathematical circle... ;-)
"Flyin' in just a sweet place,
Never been known to fail..."
Math is nuts. All those points and lines that can't exist outside of Flatland
“He’s not deformed, he’s just drunk!”