Slashdot Mirror
No Naked Black Holes
Science News reports on a paper to be published in Physical Review Letters in which an international team of researchers describes their computer simulation of the most violent collision imaginable: two black holes colliding head-on at nearly light-speed. Even in this extreme scenario, Roger Penrose's weak cosmic censorship hypothesis seems to hold — the resulting black hole (after the gravitational waves have died down) retains its event horizon. "Mathematically, 'naked' singularities, or those without event horizons, can exist, but physicists wouldn't know what to make of them. All known mechanisms for the formation of singularities also create an event horizon, and Penrose conjectured that there must be some physical principle — a 'cosmic censor' — that forbids singularity nakedness ..."
Oh jeez.
They're all Greek to me.
My ism, it's full of beliefs.
""Mathematically, 'naked' singularities, or those without event horizons, can exist, but physicists wouldn't know what to make of them. All known mechanisms for the formation of singularities also create an event horizon, and Penrose conjectured that there must be some physical principle â" a 'cosmic censor' â" that forbids singularity nakedness...""
Basically because there's two extreme conditions. Out here and in there. One can't help but have a boundary.
Does anyone else get sad at the thought that there are so many weird things in the universe you may not learn the answers to in your lifetime? What if everyone posting here never finds out the reason for the cosmic censor? Sort of depressing.
It's already asking a lot for nerdlings to not snicker at any reference to a "hole".
Adding in nakedness just goes beyond any reasonable expectation of restraint.
'a';DROP TABLE users; SELECT * FROM DATA WHERE name LIKE '%'... if you're reading this, it didn't work.
Penrose conjectured that there must be some physical principle â" a 'cosmic censor' â" that forbids singularity nakedness...
God, is that you?
Seems to me, most people on Slashdot likely *only* experience singularity nakedness.
Slashdot "libertarians": Small government for me, big government for those I disagree with. -1, I disagree with you
Roger Penrose is a smart guy, I wonder why he isn't as famous as other academics like Richard Dawkins. I just can't put my finger on it.
If photonst have weight, they can be effected by gravity, and a black hole can form around any object with sufficient mass to trap light. That's all there is to it. There is no magical singularity where the laws of physics break down. There doesn't need to be.
...the maximal Cauchy development of generic compact or asymptotically flat initial data is locally inextendible as a regular Lorentzian manifold.
Right?
Lemmings are silly; dinosaurs are extinct.
This isn't exactly my field, but I thought the no-hair theorem guaranteed this result. I guess the tricky part is in the transient phase.
And the boom from a black hole is usually in the form of X-rays or gamma rays radiation and, in energetic terms, it's very loud.
Doesn't it make you feel good to know that our freedoms are protected by politicans, lawyers and journalists.
Quantum physics was baffling to me (still is, actually), but I eventually came to see it as a way that nature avoided some inherent paradoxes and contradictions that were present when you took classic physics down to the level of fundamental particles. I have no doubt that, on a larger scale, the same principle applies: Somehow, someway, the laws of physics will always resolve with no singularities, no contradictions, no divide-by-zero-error, no infinities. If our formulas seem to indicate that one will be found, I suspect our understanding is incomplete.
Naked God.
That's heavy, Doc.
In other words, yo momma's so fat, her Schwarzchild radius is visible to the naked eye?
Which is why the DVDs "Physicists Gone Wild" were never really successful. Although the LHC did turn up as the hottest collider in Europe, so far still no naked singularities.
It must have been something you assimilated. . . .
Why doesn't a black hole collapse onto itself and disappear since it attracts everything in its vicinity? IOW, why do black holes have sizes? Assuming a black hole is not a figment of nerds' imagination, that is. LOL.
Sorry, but what exactly is a value or point of such a huge amount of absolute speculation?! The weak cosmic censorship hypothesis holds, ummm was there any surprise that it held within our limited understanding of the phenomenas parameters in a computer enviroment built on the same assumptions, we made the result fit our hypothesis of the way things are. This is just a purely speculative mathematical spankfest with no real tangible result. Two black holes colliding head-on at nearly light-speed... WTF?!?! At nearly light speed?! Golly, was it in 3D?! Does anyone else see the absurdity of this pseudoscintific masturbation? Not to make light of this but it would have been more quantifiable and practical if the "two black holes colliding head-on" were in a porno movie at slightly above average body temperature with a Bowchikawowwow backbeat?
Confucius say "Physicist who say there is no naked singularity should examine their equations through a peep hole."
Fascism trolls keeping me up every night. When I starts a preachin', he HITS ME WITH HIS REICH!
You had me at naked...
Saw the video. Can we call it the Eye of Harmony effect? lol.
This means that not only are we living in a simulation, but we're being run on a digital computer.
Anything that starts with
"Friends,"
is likely homosexual in itself. What a schmuck.
Maybe you could look up "event horizon" and see that it has nothing to do with the physical size of stuff. It's just the distance from some item of mass where the escape velocity from its gravity is equal to the speed of light.
And of course the "collapse into itself and disappear" is the entire singularity problem (except it doesn't disappear - there's that silly law of thermodynamics and matter/energy equivalence to get in the way)...
I can't get over this sort of story. "We programmed our INCOMPLETE understanding of the cosmos into this simulation, which tells us X, therefore X is more likely."
Anything based on a computer simulation is based on our arbitrarily incomplete knowledge. To base even the least significant conclusions upon it seems laughably irresponsible and unscientific.
But hey, I was a music major, so what do I know.
The United States of America: We do what we must because we can.
Touching is Transitive. Pay attention.
Comment removed based on user account deletion
I don't understand the relevance of this article. The authors themselves say that counterexamples have no way of coming into existence. Is someone implying that LHC can do this? What nonsense... The whole point of the LHC is to provide the data where the standard model might seem a little shaky. It is then and only then that we should let the theorists out of their cages!
...the most violent collision imaginable: two black holes colliding head-on at nearly light-speed.
What about 3 black holes colliding head-on at nearly light-speed?
for stuff like this if scientists are still figuring out the physics of black holes?
Don't worry, there is a a 'cosmic censor' (that's probably that guy that doesn't mod you up if you talk evolution theory).
Show a man some news, distract him for an hour. Show a man some mod points, distract him for the rest of his life.
All the mass of a black hole is compacted into an extremely small region at the centre - possibly infinitely small, but at the very least as small as physics allows matter to get. This is the singularity.
When we speak of the size of a black hole, we're actually referring to the region around that central object from which nothing can escape. As you approach the black hole, the gravitational field gets stronger and stronger, and there's a point of no return at which the escape velocity reaches c, the speed of light. Nothing nearer the hole than this can ever escape. This we call the event horizon - because no events beyond the horizon can ever be observed from outside. The more massive the hole, the further out the event horizon: look up 'Schwarzschild radius' for the equation.
The result of this is that any singularities in the universe are expected to be hidden behind event horizons, and cannot be seen. It's occasionally suggested that a naked singularity might form - for instance, a black hole might be spinning so fast as to counteract the effect of gravity and allow the singularity to be viewed from outside. This could have extremely bizarre results for the universe as a whole, so most physicists expect there to be some kind of 'cosmic censorship' principle that ensures that this does not happen. What we're looking at here is one way in which that might happen.
Real Daleks don't climb stairs - they level the building.
All objects in the universe have the right to be naked. I for one plan to fight this illegal and Machiavellian cosmic censorship, especially for all the heavenly bodies right here on Earth.
Always proofread carefully to see if you any words out.
I get a sad feeling thinking about the poor photons on the event horizons, desperately trying to escape, but suspended in space for all eternity.
Because there aren't three black hole colliding - there are two black holes colliding and then a third one colliding into the result. Remember they are travelling at the almost speed of light so the collision won't take very long.
Well, their time slows down because of the massive gravity. So eternity here could be only couple of seconds there :)
You don't know what you don't know.
But if time is moving infinitely slow, then how does matter ever get to the center? Shouldn't all the matter be concentrated at the event horizon?
Eh, Penrose is an idiot. And no, this is not intended as flamebait; but he's basically doing the exact opposite of what science actually should work like.
When faced with something that current theories can't explain satisfactorily, instead of either trying to gather more data to see whether it really is true or trying to expand those theories to provide the missing explanation, he simply conjures a deus ex machina to provide the missing explanation.
There don't seem to be any naked singularities? Well, obviously, that's because nature doesn't like naked singularities. But that's worthless, just as it would've been worthless if Newton had said "things fall down because nature likes it that way". It's essentially just a restating of the fact itself, with an additional is->ought fallacy slapped on.
Time appears slow to the outside observer, for the object crossing the horizon it's business as usual, super fast acceleration, stretched out and sucked into oblivion. Lovely :)
But black holes exist within the universe. If time inside a black hole is stopped relative to the rest of the universe, then shouldn't a black hole take infinitely long to form?
As a corollary, shouldn't you be able to look behind you and watch the end of the universe?
I'll take the second point first. And believe me I'm no expert, I mearly take an interest in Astronomy and I've read quite a lot on the subject.
If you 'look' behind you as you enter a black hole you see the light that was entering immediately behind you so you see the static universe as you normally would. But as with a lot of complicated maths and physics, human language and common experience can't really serve as a metaphor for what is going on. It's an unfortunate answer to a great many questions.
Your first question I'm not too sure about, it is a very insightful question. After a black hole is formed then yeah, time slows down to a crawl *if* there was any way to look in (past the event horizon). But I don't really know how to explain the fact that as it creates a sigularity time should slow down. I think an important concept to understand is that there is no universal clock. Imagine everyone in different gravity wells running along different percieved time-scales and you be along the right tracks. Really I'm in over my head though!
Try here for an excellent podcast on black holes and the notes page has a ton of links. This is were I get most of my Astronomy info. The podcast really will stretch your immagination!
http://www.astronomycast.com/black-holes/episode-18-black-holes-big-and-small/
...and this might begin to answer your question but I still find it hard to understand!
http://cosmology.berkeley.edu/Education/BHfaq.html#q4
Fixing that Coolant leak, I think you guys are just trying to install a Black hole collider. Since you heard of this, no more tiny weenie protons. Black holes are hot now.
Slightly offtopic, but when we say light cannot escape the gravitational pull of a black hole (past the event horizon), do we mean all electromagnetic energy? And if so, how is hawking radiation able to escape? Is it emitted by the singularity (inside the horizon) or by some phenomenon outside the event horizon?
Since the most common model for the creation of a naked singularity involves a rapidly spinning black hole, I fail to understand why there should be any expectation that colliding two black holes head-on would have that effect. This sounds like pseudo-science... "look, something that wasn't expected to create a naked singularity doesn't seem to do that in a simulation, so they can't exist!"
"I'll take the second point first"
That's it - fuck with time - mess up the chronology. Now I have to look over my shoulder, in two mirrors to read the questions in the right order to match your answers. Oh thanks very much.
A photon is not subjected to the flow of time at all since it travels at the speed of light, and thus has a time dilation factor of infinity compared with any other frame of reference.
So pity not the photon, for even an eternity is less than a moment to it.
The infinitely slow time if for an observer at the event horizon, i.e. a particle falling in percieves an eternity to pass before(?) it actually falls in. For an observer outside, time actually does pass and the particle does fall into the black hole - although he can see the particle "age" on the way in.
Yes, we do mean all electromagnetic radiation, since it all moves at the speed of light. Hawking radiation comes from near the event horizon, it occurs when virtual electron-positron pairs are created and one of the two particles is sucked into the black hole while the other escapes before they can annihilate.
Perhaps someone could educate me here but how accurate is this because surely we've never done any study into the effects of gravity at the speed of light. Doesn't gravity act differently at this speed?
Dude, that's so lame. For jokes about black holes, look no farther than the uncyclopedia.
Black hole
Event Horizon
Albert Einstein
Stephen Hawking
And of course we can't forget YOUR MOM!
No go away or I shall taunt you again.
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According to TFA, the collision releases a massive shockwave of gravitational waves and x-rays equal in some simulations to 14% of the mass of the black hole(s). Isn't this information from behind/beyond the event horizon? I've never quite understood how x-rays could 'escape' the event horizon if there is such a thing as an event horizon. Or am I misunderstanding TFA and black holes/x-rays. Cheers.
The article overviews two scenarios: a head-on collision and a collision that was not head-on. If black holes are singularities how can any collision between two black holes be anything other than head-on?
a black hole might be spinning so fast as to counteract the effect of gravity and allow the singularity to be viewed from outside
Would the hole spin over the speed of light in the case of "nakedness"? What would a circumferential velocity mean for an object of zero radius (singularity)? Would this implicate a non-zero size "singularity"?
So...how long before CBS bitches that the black holes are using their logo without permission?
Okay, so, I think I kinda understand singularity and event horizon. So, lets say we're observing a black hole from a point *inside* the event horizon.
Would then the singularity be seen as a naked singularity?
Or would there be another event horizon that applies to that internal point of reference?
You misunderstand how gravity works in GR. It's an inherent property of space rather than something that is radiated from masses. So, once the well is formed you have to un-form it to get rid of it. The singularities might well disappear when they are formed but considering that the well is infinite it takes a fair bit of time for us to experience the result.
"Oh lookie! A book I've bever read, I think I'll make fun of it!"
You show your ignorance, child. Before you mock a book you should at least read a little of it.
Genesis 1:10- And he said, I heard thy voice in the garden, and I was afraid, because I was naked; and I hid myself. 11 And he said, Who told thee that thou wast naked? Hast thou eaten of the tree, whereof I commanded thee that thou shouldest not eat?
Job 1:20 - Then Job arose, and rent his mantle, and shaved his head, and fell down upon the ground, and worshipped, 1:21 And said, Naked came I out of my mother's womb, and naked shall I return thither: the LORD gave, and the LORD hath taken away; blessed be the name of the LORD.
1:22 In all this Job sinned not, nor charged God foolishly.
Ezekiel 16:7 - I have caused thee to multiply as the bud of the field, and thou hast increased and waxen great, and thou art come to excellent ornaments: thy breasts are fashioned, and thine hair is grown, whereas thou wast naked and bare.
There is nothing sinful about nudity. You were born naked. When nudity is concerned, the only sinner is the prude.
Free Martian Whores!
Since when did Ashcroft get involved with astrophysics?
Kwisatz Haderach
Sell the spice to CHOAM
This Mahdi took Shaddam's Throne
What confuses me about this is that the spin rate of the black hole does not affect its mass, and the gravity is a function of the mass and your distance to that mass. So how does this work? I'm familiar with something called "frame dragging" where a spinning mass distorts spacetime in a way that a non-spinning mass doesn't. Is this involved here?
And along what axis is it naked? Let me reason this out: Along the plane of the spin, the frame dragging is (I'm guessing) counteracting the effects of gravity. Spin fast enough, and the singularity is visible along that plane. As you move around the black hole to observe it from along the axis of spin, the lack of frame dragging makes the black hole no longer observable. Is this on track?
IANAP, (I'm not a physicist), however, I think they are looking for a naked black hole at the wrong scale. They should be looking for naked black holes at the miniature scale, where the matter is so compact that it is classified as a black hole, however mass of such black hole is so small that it does not exert sufficient gravitational pull. Say the kind predicted within the LHC.
It's not really like many (if any) of us is doing anything to change that outcome :-/
Boot Windows, Linux, and ESX over the network for free.
Just to add to this, This is how naked singularities were explained to me:
Going back to the old image of spacetime as a rubber sheet, and our neutron star as a bowling ball on it. You're trying to escape from this, but the walls you're trying to climb up are very steep - it'd be easier to escape if the walls were shallower.
You happen to be in luck, a large planet is heading towards your neutron star and is going to crash into it. As it gets sufficiently near to the neutron star the rubber sheet that is spacetime has the gradient changed so that at any point it is less steep. There is still the same amount of delta-v needed, but at any point the requirements are potentially significantly lower.
If you can picture that, that 2 objects would make the previously inescapable 1st object escapable then perhaps the same applies to light.
So reducing the level of abstraction, would a sufficiently mass colliding with a black hole distort spacetime in such a way as push the swartzchild radius back inside the singularity, and therefore allow light to escape from the singularity?
My understanding was that a mass near a black hole would reduce its swartzchild radius near that mass, so it was all a question of could you reduce it enough before the mass was consumed?
"The weirdest thing about a mind, is that every answer that you find, is the basis of a brand new cliche" -
This wasn't a good test for cosmic censorship, and wasn't intended as such, from my reading of TFA. A better test would have been two counter rotating holes striking slightly off center.
Anyway, it says nothing about unrelated simulations that have shown that naked singularities are likely.
Sorry about the new scientist link, but all the other references I found were unhelpful journal articles.
Those people who think they know everything are a great annoyance to those of us who do. (Isaac Asimov)
Whatever happened to the naked singularities from a football theory?
(T>t && O(n)--) == sqrt(666)
Ah yes, Uncyclopedia: The unfunny version of Encylopedia Dramatica.
ED of course has an article on Uncyclopedia that pretty much shows how stupid the latter is... whereas Uncyclopedia just links ED to their Goatse article because they can't think of what to say.
-1, Unfalsifiable
+1, Simple
For example, assuming digital physics would handily explain Heisenberg uncertainty as an effect of dither noise.
Will you cut the innuendo, please? Christian creationists have a hard time following already, using repelling sexual imagery is not going to help!
Do not trust this signature.
I was more worried about this stirring the gnaa posters from their slumber...
n/t
A work that expires before its copyright never enters the public domain and thus enjoys eternal copyright protection.
The key is: vacuum is not empty.. because of the uncertainty principle, it is full of random short-lived energy fluctuations ('virtual particles'). Imagine that at the event horizon, a matter-antimatter pair is created in such an energy fluctuation, and one particle of this pair manages to quantum mechanically 'tunnel out' of the horizon, causing the BH to lose mass. That's a simplified view of the basic mechanism.
But black holes exist within the universe. If time inside a black hole is stopped relative to the rest of the universe, then shouldn't a black hole take infinitely long to form?
As a corollary, shouldn't you be able to look behind you and watch the end of the universe?
Yes. Suppose you are watching a star collapse into a black hole. First you will see the star get smaller and smaller. At the same time, the light coming from the star will become increasingly more red shifted. As the star reaches its Schwarzchild radius, it will slow down indefinitely and be infinitely red shifted. So it does take infinitely long to form from an outside observer. The Event horizon happens to be the infinitely red-shifted surface of the star. See here for a better explanation and some animated gifs: http://casa.colorado.edu/~ajsh/collapse.html
I clickled your link and who did I see? OJ Simpson and and an NSFW popup. I looked up "black hole" and came up dry.I looked up Stephen Hawking and saw nothing funny at all, just lame insults.
That popup is extremely unfunny. Uncyclopedia has me laughing out loud at times (the article about kitten huffing is priceless), and NSFW articles are noted at the top of NSFW pages.
Your dramatica is LAME. Uber lame. Commercially lame. I can certainly see why you posted anonymously.
Free Martian Whores!
I'm just curiouse what the event horizon for a black hole must really look like. Most of the images I have seen portray it as a 2D object in space, makes sense seeing as we will preceive it as a 2D object but of course it must be a 3D object. So the event horizon shouldn't be exactly flat as most pictures have to show it. I was wondering if there is a 3D picture that has been simulated to show the event horizon as I think it would be interesting to see how everything is sucked in if they have poles that pull harder than other areas it seems like something interesting.
not to mention collision. the entire first part of the post was full of sexual enuendo.
Computer simulation of the most violent collision imaginable two black holes colliding head-on at nearly light-speed . Even in this extreme scenario, Roger Penrose's weak cosmic censorship hypothesis seems to hold â" the resulting black hole (after the gravitational waves have died down) retains its event horizon. (yeah you know what their getting at)
But if time is moving infinitely slow, then how does matter ever get to the center? Shouldn't all the matter be concentrated at the event horizon?
Nature has an interesting approach to this apparent paradox. As difficult as it is to imagine, time and space "swap" places after entering the event horizon of a black hole, ensuring that you'll eventually hit the centre -- regardless of what direction you're traveling inside the event horizon. The higher your speed, the faster you'll reach the centre.
It's like trying to avoid next Tuesday.
Time appears slow to the outside observer, for the object crossing the horizon it's business as usual, super fast acceleration, stretched out and sucked into oblivion. Lovely :)
Depending on the size of the event horizon, you may not even know you crossed it. Only smaller black holes will give you super fast acceleration, stretched out and suck you into oblivion.
The larger ones are more devious and draw you in slowly... you're already well past the point of no return before you realize you're even in trouble.
But black holes exist within the universe. If time inside a black hole is stopped relative to the rest of the universe, then shouldn't a black hole take infinitely long to form?
As a corollary, shouldn't you be able to look behind you and watch the end of the universe?
Essentially, yes... if you were able to "look out" onto the surrounding universe, the further you got into the gravity well, the faster the universe would appear to be aging.
If we are in a closed universe, you'd eventually see everything rushing towards you and compacting together (then you'd all be in the same temporal reference frame and things would return to normal temporally). If we are in an open universe, you'd see the heat death of the universe first, then your black hole would slowly start lose mass and cool, as time "speeds up" to match the rest of the now dead universe, since your gravity well is now evaporating.
In a closed universe, black holes will likely be the last sources of heat (and therefore energy) left in the universe.
What if you use a large mass of magnetic monopole instead of another blackhole?
That has to be one of the finest examples of gangsta-geek humor since the dawn of Mc Hawking.
Read "Gateway" by Frederik Pohl and weep...
No sig for the moment.
The object in the middle won't be travelling at (almost) the speed of light - at least not in any direction which is head on to any of the other two objects
But black holes exist within the universe. If time inside a black hole is stopped relative to the rest of the universe, then shouldn't a black hole take infinitely long to form?
Everyone remembers time dilation, but forgets about length contraction. When you cross the event horizon, your time is slowed with respect to the rest of the universe AND your distance to the singularity is shorter from your perspective than it is from an outsider looking in.
We can't look inside the event horizon, because no light escapes. However, if we could, even if we never saw objects approach the singularity because their time has "stopped" with respect to ours, from their perspective, if the time dilation is that great, the distance to the singularity would be essentially zero. They'd be there.
As a corollary, shouldn't you be able to look behind you and watch the end of the universe?
"My Stars! Its full of God!"
No sig for the moment.
Just because math and physics don't match up perfectly, doesn't mean we have to call the result "God," nor to allude to such as "cosmic censorship." That just confuses all those idiots who already are inclined to point at anything we don't know and call that magic/god. Perhaps it would be better to call it the "we don't know yet" principle, since anything cleverer is lost on the massless.
If we shot enough stars across the event horizon, would that give the singularity enough momentum to partthe veil?
How many times must the LHC fail to get started before we see the guiding hand of God telling us not to destroy the universe?
The newsletter of the Virginia Tech chapter of the Society of Physics Students is (or was) called "The Naked Singularity."
I suppose we could call this the cosmic emergency restraining order hypothesis? ;^)
Couldn't you just stick to quoting uncyclopedia at us all the time? It's no more entertaining, but at least it's predictably stupid instead of unpredictably so.
Well even if there's all atoms or all energy. There's still one issue. A black hole should grow since matter nor energy is destroyed.
A photon is not subjected to the flow of time at all since it travels at the speed of light, and thus has a time dilation factor of infinity compared with any other frame of reference.
So pity not the photon, for even an eternity is less than a moment to it.
The same thing applies to every massive particle too. Since the escape velocity at the Schwarzschild radius is c, it follows that any particle that falls in from rest has a speed of c at the Schwarzschild radius too.
thegodmovie.com - watch it
But if time is moving infinitely slow, then how does matter ever get to the center? Shouldn't all the matter be concentrated at the event horizon?
No. Seen from the frame of the falling matter, it never stops. This only appears to be the case because time is dilated to zero at the Schwarzschild radius (because matter reaches light speed there, as seen from an external inertial frame.)
thegodmovie.com - watch it
Could this explain the double split experiment with single photons?
Do you ever get the feeling that they choose stories and phrase summaries a certain way JUST so we'll have plenty of ways to make jokes about it?
10 FILL MUG WITH COFFEE
20 DRINK COFFEE
30 GOTO 10
So to summarize your post...
"zomg lesbian sex!!11one"
10 FILL MUG WITH COFFEE
20 DRINK COFFEE
30 GOTO 10
That's awesome!
So, that Job was one bad-ass motherfucking skinhead?
Only in a Newtonian system. The subjective distance between you and the singularity would shrink from your frame of reference due to Lorentz contraction. If you counted out the seconds compared to the same distance from the black holes' frame of reference, you would believe that you were travelling at c.
But taking only data from any frame one of reference, you only approach c asymptotically.
The whole theory of relativity is based on the observed fact that light travels at c when observed from any frame of reference. This implies that only light(or other massless particles) can travel at the speed of light.
I'm sure someone can explain this in more understandable terms, but I can say that if we assume that objects can travel at c we open up a whole can of mathematical impossibilities which downright disproves the assumption.
The double slit experiment works fine with single electrons as well. As for an explanation, well there's still a debate about that. We understand how it works, we just aren't really clear about why.
Damn, that's a good one!
1 Earth is warming, 2 It's us, 3 it's royally bad, 4 we need to take action NOW
not in Ohio: you still sign up a few times if you want. Wait to see what happens in November; mark my words.
-------- Of all the things I've lost, I miss my mind the most. --Ozzy
This coward just masterfully trolled and flamebaited (ahem) at least half a dozen issues, and most of his rant was completely false and was utterly misinformed.
He deserves some sort of award, seriously.
"The greatest obstacle to discovery is not ignorance - it is the illusion of knowledge." - Daniel Boorstin
But if that was the case, fat women would be attracting men at a much higher rate than single women ;-)
Dave
Our lives begin to end the day we become silent about things that matter. --Martin Luther King Jr.
Wasn't this settled, oh, a DECADE ago, when some simulations showed that yes, there could be naked singularities formed? It doesn't matter how many scenarios don't create one, if one scenario does, then the theory allows for it (whether the real universe does or not).
NYT story on naked singularity bet
(Research on this comment consisted of one query to google, keywords "naked singularity")
BTW, "naked black hole" is a contradiction in terms. A naked singularity is, by definition, not a black hole.
Isn't the definition of "black hole" something that is so heavy and small that even light cannot escape from it?
And isn't the definition of "event horizon" the boundary beyond which we cannot observe anything, because no light can escape from it?
Wouldn't it follow from those definitions that black holes must have an event horizon? I mean, if they didn't, that would mean there was no boundary beyond which we could not see. Ergo, light would escape from them. Therefore, they wouldn't be black holes.
Please correct me if I got my facts wrong.
It all depends on your reference frame. You can write the Schwarzschild metric (the mathematical description of a non-rotating, non-electrically charged black hole) in such a way that nothing at all unusual happens at the event horizon and matter falls all the way into the center. Looking at it from the outside, with our conventional way of measuring time, it does actually look like infalling matter stops at the event horizon (though the light coming from it gets infinitely redshifted, too). The world outside the event horizon behaves the same way no matter where the mass is located, in any case.
I would rather be killed by a terrorist than enslaved by my government.
Just as long as you don't think you're one of those 'heavenly bodies', you may be able to garner some support for that.
God is dead -- Nietzsche
Nietzsche is dead -- God
Zombie Nietzsche lives! -- Zombie Nietzsche
Talking about how to take funny out of a comment which contains deliberate errors trying to make it funny ;)
You don't know what you don't know.
Yo, he be coo' wid dat shit!
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