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Black Holes 'Do Not Exist,' Contends Physicist
SpaceAdmiral writes "Nature reports that, according to a physicist at the Lawrence Livermore National Laboratory in California, 'It's a near certainty that black holes don't exist.' George Chapline argues that the collapse of massive stars is more likely to lead to dark energy stars. These dark energy stars behave somewhat like a black hole outside of the surface, but the negative gravity inside could cause matter to 'bounce back out again.'"
I've been fooled by Captain Kirk and Mr. Spock all these years. DOH!
Here is his actual article (PDF).
Perhaps stars really do collapse and that energy forms a new star composed entirely of "dark matter". It just seems a bit odd. Didn't LANL or BNL create a black hole for a few seconds, several times? Are they denying their findings or simply restructuring them?
shop.envescent.com - Computer hardware and more.
I never know if this is one of those messages that you never hear about again, or if it's one of those that you will remeber reading in 20 years, because it meant so much...
If this is totally true, i will mean a paradigm shift, a new way of thinking..but I still wouldn't want to be near a collapsing star..
Is dark energy "negative" energy? If so, if one could find a way how to get dark energy, the alcubierre drive could become a reality in the far future? I know that it need heaps of negative energy, but afaik someone corrected the calculations, resulting in much less energy consumption.
This sig does not contain any SCO code.
And I guess you are going to tell me that fairies don't exist next, right? Wake up and smell the coffee, my friend.
I always save my last mod point to mod up a good troll. You people are too serious.
Theres always someone who has a diferent theory.
On the other hand though...
Tell someone there are a million stars in the sky and they'll believe you...
Tell them paint is wet and...
http://www.sandstorming.com
Who is gonna believe a guy called 'Chapiline' about physics??? What's next, Monty Python about analytic philosophy???
I contend that ass holes don't exist!
Oh yeah? Proof by contradiction; you.
Where do you think income tax goes?
If only!
Boffoonery - downloadable Comedy Benefit for Bletchley Park
One day before ...?
You know MC Hawking isn't going to stand for this shit.
Are Outta Sight!!!
Crackpottery in high places is the most dangerous form of crackpottery because it can lead to a wild goose chase that lasts a thousand years. Lately, many of the mystical (unexplainable) stuff from the high priests of academia seem like voodoo science to me. It's the kind of stuff religions are made of. Black holes, wormholes, time travel, parallel universes, quantum computers, string theory are just a few that fall into this category. Just one man's opinion, of course.
Apparently they look something like this
In other news, donuts almost certainly don't exist. Instead it is much more likely that there exists circular pieces of cooked dough with a hole in the centre.
This idea that "singularities" don't really exist has been around for a few years now. The idea is that a very small bubble forms that is unable to compress into a singularity because of the "dark energy" concept of reverse-gravity. However, the new theories that "dark energy" really doesn't exist, and that the expansion of the universe can be explained by the negative higgs field + spacetime ripples of the early inflation of the universe run contrary to this "no black hole" concept.
Someone you trust is one of us.
The odd thing is... it will be quite impossible to prove or disprove this either way for... quite a long time.
At least until a space cruise ship christened the "Titanic" gets too close to that blackish.. hole-ish thing while taking a shortcut, in about a thousand years.
How does that come about? Integer overflow error?
... that leaves the wormholes out of the picture, too?
Great, first they take time travel away, then no interstellar voyages either...
Ministry of Disinformation works well, Lord Dark Vador...
(Sorry my bad French) Je fais parler les Guignols de l'Info. Le pied, quoi.
As much as I am happy to see that scientists are still questioning the nature of black holes, somehow I think this guy is just guessing. After Hawking recently revised his model of Black Holes to allow for information to be released (the "BHs have hair" model).
About the only interesting idea for me in Chapline's model is that of the "phase transition" of space-time.
I've got a bad attitude and karma to burn. Go ahead. Mod me down.
What did they do?: http://science.slashdot.org/article.pl?sid=05/03/1 7/1541230&from=rss
>Linux is not user-friendly.
It _is_ user-friendly. It is not ignorant-friendly and idiot-friendly.
These physicists need to get thier story straight. Some say dark energy doesnt exist and other say that black holes dont exist.
If you can read this sig - the bitch fell off.
I mean , I have never felt "confortable" with the theory of black holes, it seems somewhat anthemic to true science, kind of like phlogiston
Good Heavens, people. It's 8:30 on a Monday morning where I am. Can't we talk about donuts or something, at least until 10?
Before, I had the chance of getting sucked through a blackhole and spit out into a sister universe in some array of energy and mass, but, now I get bounced back in the form of Positron? Sweet. Then I acquire the Autobot Matrix of Leadership, and destruction of the Decepticons will be for sure! But seriously, I think this guy just has a vendetta against Rush for writing a song about Cygnus X-1.
Lets test it! Throw in a probe and see what happens to it's movements..
I like muppets.
Over the past few years, observations of the motions of galaxies have shown that some 70% the Universe seems to be composed of a strange 'dark energy' that is driving the Universe's accelerating expansion
Ah, but I at least one theory exists that says dark energy isn't really needed.
Not there's anything wrong with having different theories, we'll let observational data sort it out later. Could a physicist around here explain how these proposed dark energy stars could explain the expansion of the universe if they behave exactly like black holes outside the event horizon?
Warning: Opinions known to be heavily biased.
The researcher is claiming that his theory accounts for both dark matter and dark energy, as well as some observations like x-ray bursts from the cores of active galaxies.
Conventional theory doesn't tie dark matter to dark energy at all. If the popularizations hadn't used the word dark in both cases, the two concepts would easily be completely unrelated.
Several candidates for dark matter are very conventional forms of matter, such as neutrinos or even plain old neutronium, which don't need an exotic explanation. Others involve particles we have produced in accelerators or theorize on the basis of data we have obtained ever since the 1940's.
Dark Energy, o.t.o.h., is something very different. The evidence for it is all very recent, and the theories proposed are all well outside the standard model for Cosmology.
Thinking we even need a single theory to explain both only makes sense if you can first disprove the more conventional explanations for dark matter.
Who is John Cabal?
After calling bullshit on a recent /. thread related to dark matter, I did the math myself. There is no reason to "invent" dark matter to account for the flat galactic rotation curves. A recent /. story also says physicists have decided there is no need for "dark energy" either. These guys need to stop making shit up. Anyone who mentions dark energy or matter automatically gets put on my "quack" list. Not to mention people who submit them to slashdot.
I think Hemos forgot to post this one on Friday...
If the event horizon is a function of gravity, shouldn't it be easy to escape a black hole using a magetic drive? Last I checked magnatism was orders of magnitude stronger than gravity. This means there are 2 event horizons, one for gravity and the other for magnetism. It should be possible to escape a black hole up to the point of the magnetic event horizon. (I assume the black hole generates a magnetic field. If not then, using mag drives should allow one to navigate freely.)
Just a thought...
Slashdot's rate-of-post filter: Preventing you from posting too many great ideas at once.
Uhm, and how do i travel through time without black holes? Explain this!
This claim is about as credible in the physics world as "Apple is dying" would be in the tech community. People sometimes just spout off crazy bullshit to get attention. If the press would stop giving it to them, they'd just go away and we could get on with the business of figuring out what's really going on in the universe.
You forgot to carry the one.
Black Holes MUST exist! Otherwise, the time I spent many years ago watching that Disney Epic, "Black Hole ", was completely wasted!
nor unexplainable. black holes, quantum computation and string theory are all well explored and worked out with what knowledge we currently have. However, as this knowledge expands, sometimes the theories must be changed or expanded. After all, even the classic laws of physics fail to hold their own in relativistic situations, thus requiring an expansion.
Nothing crackpot about that, at all. Unless you expect some kind of Final Truth... and thats pretty crackpot.
-
You going to tell me that Terra isn't flat? That the humours don't control disease? That there are no dragons off the edge of the map? Puh-leeze.
This is why I make it a point to never listen to scientists. They change their minds too often. You'd think women would dominate science, considering their natural talents in that area.
http://xkcd.com/386/
Obviously, someone has to go look. I can think of a number of highly qualified people whose absense here could be, well let's say, tolerated.
What keeps me going is my inertia.
If this is true I'm kinda sad about it.
Without blackholes we lose all kinds of fun possibilities. No wormholes or time travel or moving to other dimensions.
Astro-physics loses a lot of romanticisim.
sad
What was the last law that benefited people but not corporations?
No such Thing as Black Holes?
This guy never saw Goatse...
_ _ _ Go for the eyes Boo! GO FOR THE EYES!
what about all dem people who sez dat da moon isn't for real...
Get your torrents...
The earth sucks. QED
Tomorrow on slashdot, "news" for "nerds", stuff that "matters".
http://xkcd.com/386/
One day I'm reading an article about how dark matter doesn't need to exist to explain the Universe. A couple days later, an article comes out saying how black holes don't exist, and they're starts made up of dark matter.
I'm sorry, but to the layperson, it looks like these bozos don't know what they're talking about.
~D
This sig has been enciphered with a one-time pad. It could say almost anything.
But Einstein didn't believe in black holes, Chapline argues. "Unfortunately", he adds, "he couldn't articulate why." At the root of the problem is the other revolutionary theory of twentieth-century physics, which Einstein also helped to formulate: quantum mechanics.
What ever happened to the "God does not play dice" Einstein quote? Einstein was a well known opponent to quantum mechanics in his time, now the article has him inventing it because he's the only physicist people know!?! lame lame lame
It may even put him in a wheel chair.
Oh, wait.
He says that electron-positron anihilation could account for the radiation observed at the center of the galaxy. The radiation produced when an electron collides with a positron is of a very specific wavelength - I think someone would have noticed if the radiation at the centre of the galaxy was at that wavelength, rather than a distribution of wavelengths in the way you would expect from a very hot object (superheated plasma in this case).
Well when I first saw this I was sceptical, but on further reflection I wondered - perhaps he isn't wrong. The world reacted with shock when Hubble provided evidence that the galaxies were moving away from each other, meaning the universe was expanding, and similarly the world was shocked when Hawking showed that matter "must" be leaving the other side of a black hole. Perhaps we will soon find that this scientist is correct in saying that black "holes" do not really exist.
What has Howard Stern been sitting next to all these years?
...then whate happens to the other sock?
not everything is a science experiment!
he's never seen my garage....
I would have expected Nature to publish at least a few equations that might support this guy's ideas, but as it is it reads like something on the 5:00 news.
Who modded this insightful? Probably someone who's never been to a conference...
Take a look at the header - this was submitted to a conference, *not* a full peer-reviewed journal. Many conferences (I know for sure most IEEE conferences are like this) limit paper submissions to 4 pages. URSI (Union Radio-Scientifique Internationale - they're just like IEEE Antennas and Propigation Society, with mostly the same members and co-host their conference) papers are even limited to 1 page for their conference. *Conference* papers really more discussion points than full blown "proofs". I'd suspect he'd follow this up with an "official" paper in one of their peer-reviewed journals.
Curious readers who don't happen to be physicists might be wondering, "What is "dark energy?"
It's something that hasn't been observed. Physicists think dark energy must exist, though, because otherwise there is no explanation for why the galaxies don't just fly off in all directions and disintegrate.
As was said by a strange old hermit: "It's an energy field created by all living things. It surrounds us and penetrates us. It binds the galaxy together."
... but I don't want to be sucked into it!
Today's weirdness is tomorrow's reason why. -- Hunter S. Thompson
I'm reasonably sure he wasn't actually referring to a scientific principle that causes all clocks (American clocks, Chinese clocks, alien clocks) to somehow operate in unison or with 100% accuracy. It's just a way of explaining that one theory says time is absolute, and another that says time can be warped and changed.
Just letting you know. You seemed upset by this.
The next comment I write will be ready soon, but subscribers can beat the rush and see it early!
Murky words, misspelled
Dark matter stars shed no light
Are we enlightened?
Isn't there some law that says one cannot prove a universal negative?
Maybe this would add further weight to Hawking's proof of the black hole information paradox. If the anti gravity bounced 'stuff' back, perhaps Hawking's equations are simply predicting this? Or maybe I'm talking crap.
As long as all these physicists can keep maligning and cussing each other in public, the grants will continue to roll in. Works the same way with physicians and lawyers.
Define "betterment". The question of whether atoms existed was once as abstract as the question of whether black holes exist; once upon a time the existance of molecules was not even suspected. Science works by asking questions and the hard questions tend to generate answers which are useful even when they don't give a complete solution to the initial problem.
Do you want artificial gravity? Well, black holes cover the sorts of issues that will one day be listed as landmarks on the road to that problem. It might take multiple lifetimes to get there so what's so wrong about getting started now?
TWW
"Encyclopedia" is to "Wikipedia" what "Library" is to "Some people at a bus stop"
The bit that gets me is the part about 'negative gravity.' Come up with a way to generate negative gravity and you've just devised the basis for a repulsor field. Now there's a household security system that really locks out the bad guys. ;)
My office has been taken over by iPod people.
fast as fast can be. you'll never catch me.
One thing that is wrong with black holes vis a vie quantum mechanics...
Such a silly mistake from a Real Scientist(tm). Vis-a-vis, perhaps?
Tiller's Rule: NEVER use a word that you've only heard and never read. You WILL look like a fool.
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
So the matter is repelled at the horizon when matter falls apart, thus the black hole cannot swallow the mass of the collapsing star? How does he get a horizon then firsthand? Without a collapse he cannot have this effect. When there is a horizon and he is right with his claims, this would only mean once formed a black hole would not grow. However, the existence of Sgr A* already proofs this is wrong, because there are no stars with 4 10^6 solar masses to form it in a collapse. It needs to be grown out of accreted material (which he claims is impossible). He also doesn't explain how the negative energy can collapse (and where it comes from). So he replaces one problem with another one.
Try making a gravity field first.
-- 'The' Lord and Master Bitman On High, Master Of All
E=mc^2
if you're gonna critique, critique the science, not the presentation.
I suppose you could have an electric version of a black hole
Not likely, and even if so, not for very long. What would hold this enormous amount of like-charged particles together? (Note: the electromagnetic force is way stronger than gravity.) But even if you had the electric equivalent of a black hole, it wouldn't last very long, because it would only attract oppositely charged particles, and they would reduce the net charge on the "hole".
Put another way, charge aggregation is a negative feedback loop, whereas mass aggregation is a positive feedback loop.
The world isn't flat?
Absolutely. That would be something of a proof of concept.
The fact that some fantastic idea come out of my head has nothing to do with any concept of reality.
My office has been taken over by iPod people.
I contend that ass holes don't exist!
Would this be a situation where one can link to goatex and have it actually be Informative?
There is no sanctuary. There is no sanctuary. SHUT UP! There is no shut up. There is no shut up.
So they say black holes do not exist?
I find their lack of faith disturbing...
Black Holes don't exist.. FACT ... By Gorden Brown.
You don't know what the practical benefits of currently theoretical science will be. There existence (or lack thereof) and state could prove or disprove theories about the nature of the universe, theories that could be much further reaching than just the black holes. Black hole theories seem often to be about much more than the black holes themselves.
Two masses (let's say BB's as in BB gun ammo) are all that exist in the universe and they are located 100 million light years apart.
Would they eventually speed toward each other at near the speed of light?
Can we say anything about the collision? Would it produce a white hole or a black hole?
Help end the use of Sigs. Tomorrow
a black hole... you say tomato(long a), I say tomato(short a)
redvsblue.com
::BANG!::
Sarge: Did you just shoot yourself in the foot?
Simmons: Yeah I do that sometimes now..
Whenever, over the ages, science seems to get too complicated, the usual answer is that it has gone off in a tangent. Most of the best theories have been elegantly simple at explaining our observations. These "discoveries" when proposed were considered revolutionary ideas. Later, when they were developed they usually were over-complicated by trying to explain everything. That's when a revolution in simplification happened and the process began from nearly scratch. Think of what happened to Keplerians' formulas and Newton's idea of gravity. They are still used today, even though they are wrong, and have been supplanted by Einstein's Theory of Gravity, because the models of Newton & Kepler are very accurate. Better yet: look at the models offered by geo-centric solar system projections. Here is one really nice animation: http://catholicoutlook.com/images/movingsolar7.gif
The idea is that once it gets too complicated all of the evolutionary ideas that get developed are probably causing more harm to the original thesis. Although the original work did a great job of explaining a certain observation when new data was added the theory had to expanded to a level of undue complexity to have weight. Then a competing and revolutionary idea was developed, seemed to match the data, and the process began anew.
I guess it's getting time for a powerful new theory. One that will get ruined in the future, since we really know so little.
Science is repsonsible for discovery of things and how they work; industry then applies that knowledge to problems. If we can understand the fundamental nature of gravity, and overcome the oil giants, your next car just may be powered by an artificial gravity engine that gets 120,000 miles to every atom of fuel.
But really what I think is most important is that we should never pass up the opportunity to investigate and learn about anything. Ignorance certainly has less application to humanity than this kind of science. Ignorance only serves the propagation of uninformed and unfounded beliefs and ideas in absence of fact.
perl -e "eval pack(q{H*},join q{},qw{70 72696e74207061636b28717b482a7d2c717b343 637323635363534323533343430617d293b})"
That would simplify the whole thing.
"My country, right or wrong; if right, to be kept right; and if wrong, to be set right." --Senator Carl Schurz (1872)
That doesn't seem to have been raised yet.
Black holes, or the objects theorized as such, are X-ray emitters. Although light does not have sufficient energy to escape, higher energy forms of radiation do. So although gravitation may play a part in forming an 'event horizon', there are other considerations as well.
I am not completely up to date on black hole theories, but I understand the basic principles of them. And to me it seems that current theories are insufficient to explain the phenomena that have been observed. Although there was one that interested me quite a bit. A theory that black holes, quasars, and radio-wave emitting objects are the same things but seen from different angles.
This is not a sig.
Four pages is all it should take to briefly introduce a new theory, which is what George is doing.
p.s. George Chapline is very a bright fella with a history of suggesting contrarian theories. At least one of those theories has led to a entire branch of nuclear physics.
It may or may not be bad form to prove Einstein wrong, but few have done it credibly.
Did he have a position on Black Holes?
I have been a user for about 10 years. This ends Feb 2014. The site's been ruined. I'm off. Dice, FU
....We think. I mean, we're pretty sure....kinda.... If we are right the matter might "bounce back out"....or not....we are not certain.... But I'm pretty sure black holes don't exist.
"The saddest words of mice and men, are not those which were, but should have been."
You mean Old B.O.B died for nothing? Damn you, Maximillian!
You must think in Russian.
I think this guy has negative intelligence
...is that the Professor who had the bet with Hawking over Black Holes has to give his year's subscription to Penthouse back.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Is this your sarcasm detector on the floor?
A Star is someone elses black hole!
"Near the event horizon classical GR breaks down, and one needs new physics to describe the transition from the interioir to the exterior. From the point
of view of GR this transition layer must have unusual properties in order to support large stresses."
Please explain your new physics... What a gip.
Go back to building nuclear bombs.
Because wheelchair dude is going to rip you a new one.
But captain, you canna break the laws of physics.
Does this guy have any idea how long it took to convince french cosmologists that the term "black hole" was acceptable?
As I recall people had trouble beliving the world was not flat. Keep this in mind before completely discrediting one's theory.
on the inside??? 12133674
We know of at least one black hole whose existence has been repeatedly verified by unsuspecting eyes: Goatse.
Dude, are you stupid, humour challenged, or both?
The poster indicated that your girlfriend and / or her fellow male Starbucks employees wanted you to think that they were gay so that they could play with your girlfriend without you being jealous and suspicious.
Get it now? I don't think we can make it any simpler than that.
What the hell is a dark energy star. Dark energy and dark matter are entirely theoretical. We don't know what they are or how they interact. This dark energy matter stuff just exists to balance equations. Physicists are definately smoking something, they see dark matter galaxys and dark energy stars. For me its seems much easier to beleive physics works differently on a large scale.
I personally know of atleast 2 black holes, the one in my wallet, and the one in my memory from saturday night. Back on topic: I declare that light has mass, and as such is suceptible to gravity, that doesnt mean that black holes exist, but they certainly could! (and probably do)
Officially: "No comments"
Don't know much about space stuff but...
THAT'S NO MOON!
You'll get a real kick out of this thread then!
"Encyclopedia" is to "Wikipedia" what "Library" is to "Some people at a bus stop"
"The first thing to realize about black holes, [yourruinreverse] says, is that they are not black.\nIt is also important to realize that they are not, strictly speaking, holes either, but it is easiest if you don't try to realize that until a little later, after you've realized that everything you've realized up to that moment is not true."
[Adapted from Douglas Adams, Mostly Harmless]
JeR
When I see an article like this, my first thought is that either someone still thinks it's April Fools' day or the editors at Nature took Scientific American's latest editorial to heart when they published it.
he wasn't trying to be funny.
You can't handle the truth.
This would then cause all of the matter to accumulate around the black hole in this neutral zone of gravity, effectively increasing the mass of the black hole. The increase of mass would increase the amount of positive gravity causing more objects to be sucked in.
This process would continue until the black hole becomes so massive that the possibility of implosion and either a super nova like event or a mini-big bang occuring.
This is not here.
I guess this new article combined with an older article: http://science.slashdot.org/article.pl?sid=05/03/2 4/2242219&from=rss
Proves that physics is still very theoretical. Then again, I always felt that dark energy, and possibly dark matter will inevitably be proved to be about as real as the "Aether" theories. Like Cheech and Chong said in the 70's; If it looks like dog shit, smells like dog shit, and tastes like dog shit......... We always try to explain things by saying something unobservable is the factor causing the observations we can make. My uneducated guess is we will find that neither of these are necessary, and someone will be able to fill the holes.
Let's not forget that the reason why we use math to describe these phenomena is because the real world is based on mathematics. For example, there is an 'event horizon' at 1, where multiplying a number by >1 makes it larger but by <1 makes it smaller. Maybe dark matter can be described in some equation as <1 whereas 'light' matter is >1 (so dark matter interacting with light matter would diminish it). Or maybe the event horizon of a black hole is like 1 and the center is 0.
In any case these concepts (x<1<y, 0, etc) have manifestations in the real world that should not be forgetten... that's why string theory smells so wrong. Basically {0} can't be explained by the equations so they pretend it is a vector {0,n}... only then n could be zero making a zero-vector {0,0} so they add more dimensions until they are out of concepts. Doesn't sound like a winner to me.
Time dilation exists, it has been demonstrated experimentally many times, with human clocks, yes. But how come *your* _perception_ (human and imperfect, yes?) trumps atomic clocks?
Didn't we just have an article last week which stated that dark energy didn't exist?
I believe I achieve just that merely by sitting here. Let me grab a few donuts and a few more bacon and eggs breakfasts, I'll be generating even more.
An object does not have to reach escape velocity to escape a planet's gravitational pull.
;)
;)
You're partly right. You can NEVER escape a planet's gravitational pull. It just keeps pulling, no matter how far you go.
Escape velocity is the inital speed needed for a ballistic object to ensure that the gravitational pull of the planet will never be able to bring it to a complete stop, relative to the planet. As you move away from the planet, the gravitational force weakens. If you can move away faster than the force can slow you down, then the gravity of the planet can never stop you. That's the escape velocity.
However, for a rocket (or other powered device) to escape a planet's gravitational pull, as the GP said, all it has to do is provide enough vertical thrust to provide a positive acceleration. That acceleration does not have to accelerate it to the escape velocity - in fact, you could adjust it to compensate for the falling gravitational pull and so maintain a constant velocity of whatever you want, and (if you have sufficient power/fuel) you'll still escape.
In theory, you're partly correct here. If you could overcome gravity to provide a 1 foot per second squared upward accelleration, then yeah, you'd get to outer space. Eventually. It'd take one hell of a lot of fuel though, because you're only barely overcoming gravity. It's not actually *possible* because no ship exists that can do that and also have enough fuel to do it.
Any acceleration larger than gravity will get you there eventually if you assume enough fuel. And as gravity drops off due to distance, eventually you'll be travelling faster than escape velocity for the given height you happen to be at. And then you're free.
That doesn't work for a black hole because all of that is based on Newtonian mechanics, which do not apply in the large gravitational fields close to the event horizon. There, you must use General Relativity, which is counter to our everyday common sense view of the world (precisely because on our scales, it's irrelevant). I don't know enough about GR to demonstrate why this is, however.
The main reason is similar to the above: You don't have enough fuel. And not just because the technology doesn't exist, but because inside the event horizon, the acceleration due to gravity is so high that even light itself isn't moving fast enough to go "up". No amount of acceleration will let you make any forward progress at all, because you cannot possibly give it enough speed to exceed the speed of light. So you can't even go up at 1 foot per second, you can only go down.
To put it another way, inside the event horizon, space is bent in such a way that moving away from the singularity is no longer an available option.
Outside the event horizon, the normal, simple, equations still apply, more or less. The gravity is high, but the concept is the same. With a higher gravity comes a higher escape velocity, that's all. Also time dilation, but that's rather irrelevent to this discussion.
- Give a man a fire and he's warm for a day, but set him on fire and he's warm for the rest of his life.
You mean they told you that they loved you, but it turned out they were just using you for sex?
...
More or less. I guess I should have figured it out for myself
-- Kirk kept shouting, "Oh Janice, oh Janice!"
-- Spock only did it every seven years.
-kgj
-kgj
Why not send him on the first expedition to observe a black hole. If he bounces back, he was right.
I wish I were old enough to put "Computer" on my resume.
But what about that recent experiment where they created a mini-blackhole?
:-))
(and I don't mean this experiment
www.vanheusden.com - home of Multitail, HTTPing, CoffeeSaint, EntropyBroker, rsstail, bsod, listener, nagcon, nagi
Most Nobel Prize winning articles are one-pagers. For example Chadwick's article describing the neutron basically says, "if we apply energy and momentum conservation to the recent experiments of so-and-so, the clearest solution is a new neutral particle."
The journal Physical Review Letters (prl.aps.org) typically publishes only four-page articles.
Oh brother. I didn't even get past the first page of his paper without running into physics errors. He claims that "quantum mechanics requires a universal time". This is nonsense; quantum field theory on curved spacetime -- and, in particular, on non-stationary spacetimes which do not admit any preferred "universal time coordinate" -- is a well-developed field and is quite rigorous (as far as QFT goes); it is a proof-by-example that QM without a "universal time" does work. However, you have to accept that certain procedures of ordinary QM won't remain useful; e.g., you don't tend to work with Schroedinger equations, since, as the author does correctly point out, the Schroedinger equation posits an absolute time (and a flat space). But the Schroedinger equation isn't fundamental to quantum mechanics and is not one of the postulates of QM (heck, it's not even relativistic). You can construct canonical Hamiltonian formulations of QFT without ever referring to a Schroedinger equation.
Actually, I just continued to read more of his paper, and it seems that almost his whole argument is predicated on this false claim that "synchronous time" is incompatible with quantum theory.
His "simple thought experiment" to demonstrate why it is "wrong to assume classical GR is always correct on macroscopic length scales" does no such thing: he gives an example of a condensed matter system which is a black hole analogue (has the qualitative kinematics of an event horizon). This is also well-known, but doesn't prove that condensed matter systems can mimic the full dynamics of general relativity. Indeed, nobody has succeeded in that task (don't have a good review article, but look at the references in this paper by Visser). And even if it did prove that condensed matter systems can externally act like black holes, that doesn't prove that GR is wrong on macroscopic length scales, either.
I didn't even bother to really study the dark energy bit after these preceding flaws, but beyond that, the paper is filled with crackpot warning signs: grandiose claims (simultaneous resolution of the question of black holes, singularities, the black hole information loss paradox, dark matter, and dark energy); claims that historians will one day vindicate his obvious correctness; etc.
In short: read with an extremely large grain of salt.
I'd like to hear what S. Hawking has to say about this one.
http://www.rediff.com/news/2004/aug/03hole.htm
An indian scientist had done work to prove that black holes do not exist as Hawking has described them. Even Hawking was forced to agree. For some reason this work was given minimal press.
might be just the thing needed to warp space in such a way to create a worm hole. Before now, we never thought that could be possible. It opens up possibilities to such things as time travel, and space travel through the wormhole.
That is, if this theory is true.
Remember, Slashdot does not have a -1 disagree moderation, and no, troll, flamebait, and overrated are not substitutes.
He said any electron going in would bounce back out as a positron. Does he account for conservation of charge somehow?
The problem with black holes is that they are, by definition, singularities. Unadulterated GR says that matter becomes infinitely dense, that the event horizon is infinitely sharp, etc.
This isn't very satisfactory, and we've known for a long time that something interesting must happen to smooth out these infinities at the Planck scale (something to the tune of 10^-33 cm). In this limited sense, we've known all along that "strict" black holes don't exist: that is, the pure, mathematical singularities that GR predicts must be smoothed out by quantum effects at very short scales.
In keeping with the sloppy thinking that makes physics the Queen of the Sciences (IAAP, as it happens) we've decided that those Planck-scale effects don't really count, and implicitly modified our concept of "Black Hole" to accomodate them.
What this guy is playing with is the idea that something interesting happens on much larger scales. In this case, although there is still something like an event horizon, it is no longer a singularity in the space-time co-ordinates of distant observers, but rather a phase transition in the quantum-mechanical vaccuum. He is proposing a macroscopic quantum mechanism for smoothing out the singularity.
This is a nice move for two reasons: the study of quantum critical behavior has a variety of analogues such as superfluids that can be studied in the lab; and there are physical phenomena that he predicts which may explain a variety of otherwise problematic observations. These are: high-energy positrons from the centre of our galaxy (where there is a 10^6 solar mass dense object); gamma-ray bursts; cosmological dark matter.
Overall, this is a nice, plausible, interesting approach to a serious problem.
--Tom
Blasphemy is a human right. Blasphemophobia kills.
Wouldn't it be so much easier for y'all to just admit that God made everything, and that Jesus is shootin' around up there like the Silver Surfer, pickin' up all the broken bits? ;)
The preprint was produced with Microsoft Word under MacOSX.
I cannot trust a physicist who does not use RevTeX. At least he could have used non-Microsoft alternatives, like Nisus Writer (MacOSX) or Lyx (under MacOSX+Fink)
If you got sucked into a dark energy star, would you be turned into spaghetti?
Celebrate the finer things in life
If this guy ever met my ex-wife, he'd know that black holes truly exist.
I might know what I'm talkin' about, but then again, this is Slashdot...
Slightly offtopic, but (I hope) interesting, and something you may actually know about:
I've got a piece of technology I've worked out for a story I'm working on.
As I understand it, one theory behind the vacuum is that it is filled with "virtual particles" that pop into existance with their anti-particle somehow nearby. They collide, cancel each other out (with no release of energy? How does THAT work?) and vanish.
Is that right?
So this fictional technology (it's a warhead, actually) creates a field that supresses the generation of one of the two types of virtual particles. That generates a sudden, theoretically infinate (but practically limited ) "burst" of particles within the field limits.
Supress "normal" virtual particles, and you get a ball of antimatter, which immediately contacts the normal matter of the field generator, and BOOM!
Supress "anti" virtual particles, and you get a super-dense ball of regular matter - dense enough to create a small black hole. Trigger this near a planet or a star, and you get enough matter infall to counteract the rate of it boiling away via Hawking radiation, and chomp!
If we handwave away the mechanism behind which the field works, is the rest of this plausible?
Please discuss. I'd love to hear your take on this.
DG
Want to learn about race cars? Read my Book
many gay interracial porn movies. So we know 3 things, he is not gay, he is into some kind of religion that prohibits porn movies, and he doesnt know shit about black holes.......
and the call them a scientist.....
world if fucked up
but I'll bite. Taking your closing line at face value:
Why do you assume that real galaxy models neglect the stars in the visible disk? The plots of theory vs. observation for a number of spiral galaxies that I'm looking at right now don't make this mistake.
Why do you assume that real galactic rotation curves stop at the edge of the visible disk? The ones in front of me go out to 2-3 times the edge of the disk.
Why do you assume that varying the distribution of mass in your model can match the observed data? So far your only model is a qualitatively very bad fit, and not even remotely quantitative.
But it's good that you want to play with this. Here's a java applet that will let you play with the parameters of a simple model and match the results to real galactic rotation curves. You can adjust the central dark matter halo density, the halo core radius (how big the halo is), and the disk mass to light ratio (how much matter is in the disk). There's also some information on how it all works. Note that the contribution of the disk falls off when you get outside the disk, but the total flattens out and may even continue to increase a little.
Of course, a physicist using Microsoft software cannot be right. Hawking uses RevTeX, his theories MUST BE RIGHT.
Long live the blackholes!
Newtonian theory allows black holes. People early on put these facts together: everything subject to gravity; things move in orbits subject to an escape velocity; light appears to particles; and light appears to have a finite velocity. When all these are assembled, you could conceive of a body dense enough with a radius and escape velocity greater than the speed of light.
You know, if Google decides to host journals the page limit might be increased to 4000.
Know your pads. One time pad: good for cryptography. Two timing pad: where to take your mistress.
Maybe you should wait more than three minutes to respond to yourself?
Physicists are people too. They (I'd be tempted to say "we" but I changed majors mid-stream) don't get as hung up on vi vs. emacs or BSD vs. Linux vs. Gnu/Linux, or open vs. closed vs. I'll-let-you-peek-but-then-I'll-have-to-kill-you source operating systems. And (the ones I know at least) have never watched (let alone voted for) any one on any American-Idle type television program.
But the fundemental personality trait is still there. It comes out in things like "is space quantized at the planck scale" or "are strings real/fundemental or is string theory an artifact of something deeper". Add beer and watch the fur fly.
--MarkusQ
This proves nothing. If you are in doubt if the Earth is flat or round, how would you know that a Moon eclipse is the Earth's shadow? Alternative answer: a Moon eclipse is when a dragon swallows the Moon. The eclipse ends when the dragon vomits the Moon because the dragon *hates* the taste of cheese.
Black holes (allegedly) emit Hawking radiation so they should be detectable as a light source.
We should take 2 scientists, shoot them straight into a black hole which ever one makes it back gets to make as many laws as they want.
A loop, by its nature, continues. If that didn't make sense, start reading this sentence again.
To a far-off observer, time seems to stand still here. A spacecraft falling into a black hole would seem, to someone watching it from afar, to be stuck forever at the event horizon...
This is not the common theory. It would NOT stand still as a normal image.
I think the image of the spacecraft would shift into red until it reaches frequency zero and is no longer detectable.
An argument against the above is here. It's far better than my argument, but it just seems too crazy for an object to traverse the infinite future and come back to the present by falling into a black hole. There'd be two copies of the object in existance.
In Ye Ol' Star Trek, you travel back in time.
In Voyager, you just get turned into a giant newt. Everything else made you travel through time though.
A giant newt... the evolution of man? That's not what we'd been told by Trelane, Q and the Traveler... Wesley didn't turn into no slimy giant newt... stupid Voyager.
You can't take the sky from me...
You think that theorizing about black holes makes you less ignorant? We are all ignorant of such things and wasting time guessing about how stuff works is just pointless.
You make the mistake of thinking of light as a ballistic particle. Light *always* travels at the speed c (assuming an empty medium). Gravity can cause it to turn, but it cannot cause it to slow down. Therefore, it makes no sense to suppose that you can accelerate yourself out of a black hole when a lightbeam, which cannot be decelerated, cannot escape itself.
I think a common way of putting it is that all "world-lines" (http://en.wikipedia.org/wiki/Worldline/) end up at the singularity in the black hole. More than the light simply not "making it out" as it were getting close to the horizon but then falling back, there *simply is not path out.* Every single path the light beam can follow falls into the singularity. Similarly, no physical entity can make it out either. Spacetime is curved in such a way that you cannot go back; you can only go forward. Every meter passed is like another event horizon from which you will never return =O.
"God does not play dice with the universe"
Guess that physicist didn't read my sig.
No sig for you! Come back one year!
As I understand it, for a trillion-solar-mass black hole, gravitational acceleration at the event horizon is only about 1G.
l ight%5E4+%2F+%28gravitational+constant+*+100000000 0+solar+mass+*+4%29%29+%2F+gravity+on+earth
Don't know where you got that idea. If you assume a simple non-rotating black hole, then the Schwarzschild radius (aka the event horizon) is the distance from the singularity at which the gravitational field is so powerful that the black hole's escape velocity is greater than the speed of light. r = 2GM/c^2, where r is the Schwarzschild radius - the distance from the singularity to the event horizon. You can even get this from the Newtonian escape velocity equation, just set v = c and solve for r.
Now, plug that radius into the standard acceleration formula: a = GM / r^2.
Result: a = c^4 / 4GM. a = acceleration due to gravity at the event horizon, M = mass of black hole.
And here's a nice google query to tell you how much acceleration there would be at the event horizon of a black hole of a trillion solar masses: http://www.google.com/search?hl=en&q=%28speed+of+
So about 1551 G's. If you add more mass, the acceleration drops off, of course.
It's not that you can't accellerate hard enough to overcome gravity, but the effects of a massive object on space itself that makes a black hole inescapable.
Yes, I see your point now. Say you're in a spaceship just inside the event horizon of that trillion sun hole above, and decide to gun the engine to 2000 G's to get the hell out. Why can't you? And the answer is that it's because of a the way space is curved inside the event horizon, so yeah, Newtonian mechanics can't cover this situation. Light can't change its speed, only it's direction. You can change either one, but are still screwed for different reasons.
- Give a man a fire and he's warm for a day, but set him on fire and he's warm for the rest of his life.
Hah. I left off 3 zeros from that google query. Here's the corrected one:l ight%5E4+%2F+%28gravitational+constant+*+100000000 0000+solar+mass+*+4%29%29+%2F+gravity+on+earth
http://www.google.com/search?hl=en&q=%28speed+of+
Giving you about 1.551 G's at the event horizon. My mistake.
- Give a man a fire and he's warm for a day, but set him on fire and he's warm for the rest of his life.
First off, I don't theorize about black holes, and I don't think the act of theorizing about black holes makes any one person non-ignorant. The act of learning makes our societies less ignorant of the world around us and enables us to create more enabling technology. And if you think I'm wrong, just remember that if nobody theorized and guessed and figured out about electricity, and just stuck to the notion that it was a mystical device of the wrath of god, we'd be having this conversation by candlelight on dixie cups and fishing wire.
The idea that learning is somehow "bad" is completely incomprehensible to me.
perl -e "eval pack(q{H*},join q{},qw{70 72696e74207061636b28717b482a7d2c717b343 637323635363534323533343430617d293b})"
monopole attract like charge!!!
and the cats married the fishes and we all lived happilly ever before.
-pyrrho
and that was the error.
-pyrrho
He should at least be forced to go over to Hawking's house and hold the pictures up for him.
The type of warp field that is used in TOS-TNG era can only have 9 layers before consumption and speed approaches infinity
According to my next-gen technical manual (page 55), Gene recalibrated the warp scale so that warp 10 was the absolute top of the scale. At warp 10 speed is infinite, so it can never be reached. They estimate that the Traveler, in "Where no man has gone before", propelled the Enterprise at warp 9.9999999996.
On page 62 they explain that the "old" warp scale's fastest recorded speed was 14.1, reached by the original Enterprise in "Is there in truth no beauty?". That is 9.7 under the "new" warp scale, and the next-gen Enterprise reaches it in "Encounter at Farpoint".
Then they fucked it all up in Voyager by having them go faster than infinity, and turning them into giant newts, which is about the point in a game of table RPG where you realise that you game master (or in this case, hollywood television: your executive producer) is a munchkin, drunk with power.
You can't take the sky from me...
I know a cave somewhere in Texas, and it certainly is a black hole.
First comment to express that thought that I've seen, and it included an example.
It even has an equation.
This is my sig. It's prescription, I swear. I need it for reading things... on the other side of things
I can certainly see a large number of difficult places where a "universal time" would make things easier... but I believe that this would be very difficult to justify by any normal definition of "universal time".
As just the most obvious example, if time is running smoothly along "universal time", what causes particles to last longer if you accelerate them?
Presumably he has answers to this kind of objection, but I haven't encountered them.
I think we've pushed this "anyone can grow up to be president" thing too far.
Yeah Voyager really did screw everything up, in many, many ways. I think they were the first ones to use phasers at warp (a practice carried over to Enterprise); among many other huge problems.
One of the biggest problems with Voyager was the founding principal of the series, namely the amount of time it was supposed to take them to get home. It might have been consistent with the TNG tech manual (I'm not sure) but it certainly wasn't consistent with speed precedents set in TNG or the movies. For instance: in ST:V the Enterprise goes from Earth to the Neutral Zone to the center of the gallaxy in what could have been (at most) a month or two. In TNG and DS9 there is plenty of "too fast" travel between destinations in the alpha and beta quadrants as well.
The TNG tech manual isn't exactly authoritative when it comes to speed, BTW. The reason is that they measure warp factors in cochranes. A cochrane (as a measure of speed, its also a measure of field strength) is theoretically equal to approximately c but the actual speed varies depending on "gas density, electric and magnetic fields... and fluctuations in the subspace domain" (pg 55). One could suppose certain parts of the galaxy allow for faster travel then others, which does help Voyager's case, if for some reason the gamma quadrant slows you down or the alpha/beta quadrants speed you up (though really that's stupid).
Cool art gallery, if you're into that sort of thing.
The Flat Earth Society was once a serious and respectable society but it folded a few years back. Now anyone can set up a web domain with a name containing the words "flat earth society" and sully their name.
Doesn't it make you feel good to know that our freedoms are protected by politicans, lawyers and journalists.
Thanks for the link to the submission.
From his introduction, he seams uninformed. Off course, I'm only an amateur, so perhaps I'm missing something.
He says : "The fundamental reason for the tension between quantum mechanics and GR is the lack of a universal time in GR."
However, according to wikipedia, the standard model is "consistent with both quantum mechanics and special relativity." and "Special relativity holds that events that are simultaneous in one frame of reference need not be simultaneous in another frame of reference."
So, the standard model is a (well accepted) way to make quantum theory work without an universal time and therefor I think that this guy doesnt really know what he's writing about.
If I understand the article correctly, he says that quantum mechanics wont work in a black hole (which is true) and that if quantum mechanics are always true, there must be something else. He then constructs his model of dark matter stars.
The main problem that I see with this is that, while it is well-known that general relativity and quantum mechanics dont work toghether, he chooses to use only quantum mechanics to explain a black hole. However, quantum mechanics work badly with gravity and even worse with high gravity, so I think his article is pointless.
I have discovered a truly remarkable proof for my post which this sig is too small to contain.
For instance: in ST:V the Enterprise goes from Earth to
I'll stop you right there.
I choose to pretend that I never saw ST:V, that it never happened; it doesn't exist.
It was only a bad dream, then I woke up, and I never saw Uhura do the fan dance, or the chick with the 3 boobs, or ANY of that!
One could suppose certain parts of the galaxy allow for faster travel then others, which does help Voyager's case, if for some reason the gamma quadrant slows you down or the alpha/beta quadrants speed you up (though really that's stupid).
I'll never forgive Voyager for their cheap "Kess uses Ocampa magic to make the Voyager (btw, dammit, V'Ger... GOSH!) jump to just enough distance to get them through Borg space and replace her with a better babe to use as eye-candy and therefore getting rid of our 'wasn't she supposed to age really fast?' problem" stunt.
I mean sure, 7 was HOT. But that's no excuse.
You can't take the sky from me...
If there are none how did the star gate get stuck to a world with one?
Black holes has always been a theory and not a complete one at that. Granted the theory arises from the application of General Relativity to stellar collaspse. Since General Relativity is pretty much regarded as law, the black hole as a theory seems to be pretty solid. However, there are many fundamental questions that are unanswered. First, what happens to the individual wave functions of all nucleons that made up the star in the first place. If they all collapse to a singular point, doesn't that violate Heisenberg uncertainty principle (you know both momentum and position). Whats the wave function of the singularity? Does quantum mechanics apply (it should)? What happens to time at the singularity? Does relativity still apply? With all these questions and the fact we haven't observed stellar collapse or a black hole, we should be open to other theories and never hold something that is still heavily theoretical as canon.
You don't have to be smart to use a Mac, you just have to be smart enough to buy one
It's amazing where the actual attempts at peer review end up burried on slashdot :)
Fixing copyright
Of course, he could just be a crackpot. He'd better have some equations and data that support his hypothesis and contradict black hole theory.
God seen playing dice with the Universe, more details at 5. And in other breaking news, Schrodingers' Cat still in a simulataneous live / dead state, PETA expresses outrage, heads of right-to-lifers explode.
What if a "black hole" was simply a gravity well powered particle accelerator of the atom smashing variety? Possible? I dunno. Is there a possibility that there's just enough matter in your black hole to accelerate matter to 0.999c and collide with the surface of what was once a neutron star (in the presence of trapped photons), creating nothing but subatomic particles (dark matter???) and energy?
To me, throwing off lots of energy might help explain this universal expansion thing. Then again, I could be barking up completely the wrong eucalyptus. An interesting thought experiment nontheless. Any theories/reasons against it, or should I just sign my self into the institution now?
http://www.newpath4.com/formulaeperpetual_perpetua ltimeperpetualspaceperpetualpowerperpetualmomentum perpetualmotion_3plus4equals5.gif
Spinning, whirling,
Still descending
Like a spiral sea,
Unending
Sound and fury
Drowns my heart
Every nerve
Is torn apart....
We already know there is no concept of universal time. Special Relativity which is a lab demonstratable theory has already shown this, so the primary assumption of this paper is itself wrong. The fact that there's nothing wrong with the nonuniversality of time in SR, seems to imply that there should be no reason it's wrong with GR
Personally, I think time runs backwards inside the event horizon, as the ever-increasing energy density (from an outsider's point of view) is anentropic, and time always flows in the entropic direction. But I can't back that up. :)
Actually, if you buy Einstein's Field Equations and more specifically solution that defines the Schwarzschild metric, then it tells you that for regions close to a mass with distance that is smaller than the Schwarzschild radius, some damned odd things occur. Considered in radial coordinates, r (the radius) and t (time) swap places. r becomes timelike and t becomes spacelike. To the effect that r can no longer be held constant over any given period of increasing time. In other words, even holding your position becomes impossible. Going forward in time means going towards the singularity.
- Give a man a fire and he's warm for a day, but set him on fire and he's warm for the rest of his life.
Comment removed based on user account deletion
Slashdot sure like crackpots, for some reason.
The cryogenic captain, the Silver Surfer wannabee, the smart bomb, it's all coming back to me now. Aaaaaaaaahhhhhhhhgggggggggghhhhh! (-:
Got time? Spend some of it coding or testing
...Collapsar, appropriately enough a collapsed form of "Collapsed Star".
And yes, it does reach through a General Dynamics hull, why do you ask? (-:
Got time? Spend some of it coding or testing
Y'all think you're so cool, don't ya!
The Intelligent Design crew don't argue from silence. They argue that we have now accumulated enough observations to positively state that evolution cannot possibly have achieved certain things.
If you claim that they argue from silence, you're going to look like a complete 'tard the first time you meet one.
Got time? Spend some of it coding or testing
An ID advocate at least acknowledges that certain things are impossible for evolution to accomplish. Even if their assertion of an Intelligent Designer turns out to be wrong, they will at least look past the dogma of "arbitraro mutatia et selectae naturo omnes", which many scientists won't do.
An Evolutionist's approach is forced by his religious assumptions. Regardless of whether they're an Atheist or not, an Evolutionist has to at least assume that any putative God either won't or can't intervene in mundane affairs. This means that they are duty bound to jam everything through an Orthodox Materialism filter before accepting it. But then that have no way of telling whether Materialism itself is correct or not, or even their understanding of it. It is true by definition and therefore not falsifiable and not susceptible to scientific examination.
Got time? Spend some of it coding or testing
...is tomorrow's shredder output. Progress munches on. (-:
Heed the tale of the physics exam: tourists at a large American univeristy are being shown through the Physics Department. As the group enters, one of them notices a large document mounted in a glass case against the wall.
After the tour, back in the foyer, the guide asks "are there any questions?"
The chap raises his hand, and when called upon, indicates the document and asks, "What's this?"
The guide explains that it's their physics exam.
"What?" exclaims the horrified tourist, "Don't people cheat? Do you change the questions every year, or something?"
"No," explains the guide, "our approach is much simpler. We change the answers."
Got time? Spend some of it coding or testing
*Black Hole bends*
where... ?
-pyrrho
I'm a materialist, but I see that as a theory not a religion. I'm open to contrary evidence, but I just haven't heard of anything credible yet. There are certainly lots of ways in which materialism could potentially be falsified.
Is there anything which would convince ID proponent's they're wrong, short of an infinitely detailed materialistic explanation of everything in the world?
On the other hand, most of the ID organizations have a statement of faith that they are not prepared to consider changing, no matter what. It is a point of pride that they are not interested in contrary evidence. This insistence that their doctrine is right and above questioning is fundamentally antiscientific, and a pretty good demonstration of the difference between religion (assertion of authority) and science (search for truth).
you can derive c by using maxwells equations in differential form and integrating over an EM wave.. and you get c= 1/ (mu_0 epsilon_0)^1/2 or something...
meh
anyway so if mu and epsilon (the permebility and permeativity of free/other space to magnetic and electro forces) are different in some region then c is going to be different in that region..