Optical Black Holes in the Lab 194
spaceorb writes "According to researchers ... it may be possible to create black holes by creating a vortex of fluid that swirls at velocities comparable to the speed of light. Follow the above link for the theoretical discussion or here for the story on unisci.com." These are optical analogues of black holes, not really gravity wells, but they may advance our understanding of the real thing.
Re:This is why Science is dangerous. (Score:1)
Re:Velocity is relative (Score:1)
Superfluid black holes (Score:1)
Light (Score:3)
What this vortex will do is make that path of misdirect infinitly long (ie a cirle like). Therefor the photon will never make it back out.
This is 'simular' to the idea of refraction in optical cable, the material is such that the light is always refracted back within itself (if it enters at a certain angle). what the vortex does is make a circular optical cable with prefect refraction trapping all light within itself. (I know this is an over simplification)
Gork the Enchanter
Re:Nothing new here (Score:1)
1.4Gigs of its MP3s too.
Light == EM (Score:2)
Re:A million household uses! (Score:2)
I expect you could make a 'sonic black hole' using the same idea as this one, but the trouble is that this method doesnt seem to SUCK the light in like a gravitational black hole does. It has to hit part of the vortex to be captured.
I'll believe it when I see it (Score:3)
"doh!"
Skygate (Score:1)
Someones been watching too much TV
My favourite quote (Score:2)
Gotta be:
"A tornado, for example, attracts with ease substantial ``test particles'' such as cars"
:-)
dylan_-
--
Maintaining Liquidity (Score:2)
For one, exactly how do they propose to keep the water in liquid form?
Water remains liquid only at certain temperature/pressure ratios. Creating a vortex rather quickly creates large pressure differentials(almost by definition), and dumping light into something that isn't going to be able to spit it back out is going to increase temperature. How is the entire mass going to be kept in that one relatively small range that keeps the material liquid? Granted, an excessively smooth container might allow superheating of the fluid(water cannot boil unless there are microscopic ledges upon which bubbles may form, apparently), but having this fluid in contact with *any* other substance is going to create seriously ugly amounts of heat by way of friction.
Even supposing one could accelerate such a material to near-luminal speeds, at minimum a Zero-G environment and a vacuum would be required.
But that's one heck of a supposition! Assuming a massive objects could be spun at such extreme rates is...generous. Am I wrong, here?
I must also ask where the concept of absorption has gone. For a while there, I was imagining they were describing a merger between fiber optic cable and a roach motel--light got in, then was forced to spin round and round the vortex forever. But who said that the water would become instantly clear? As it spun around, wouldn't more and more of it be converted to heat until there was no light left? I'm not slowing down light if I move it through a fiber optic cable that's a kilometer long but on a spool only a foot thick. The light still moved a kilometer, even if (from my "perspective") it only moved a foot. But fiber optic cable is very transparent; water isn't nearly as such--particularly water that bubbles and is highly agitated.
And how would light enter the system if the outside walls of the vortex were so particularly
chaotic? This part, I'm really missing.
Something just seems...wrong here. Someone care to clue me in?
Yours Truly,
Dan Kaminsky
DoxPara Research
http://www.doxpara.com
Re:Well... (Score:1)
Re:Asymptotic Black Holes (Score:2)
Neat, but the obvious question that arises is... (Score:1)
;)
Your Working Boy,
This is bullshit. (Score:1)
It seems to me that there are some tricky special relativity thingies that these guys are forgetting.
Roger.
Re:bad physics (Score:2)
> for a particle to cross the event horizon from
> the outside perspective of an observer who is
> not falling into the hole. To the particle or an
> astronaut falling into the horizon, the trip is
> quite short. Therefore, to say that black holes
> only exist asymptotically is incorrect.
Two frames of reference:
From the perspective of the outside observer, what occurs is as described, the infalling object (albeit ripped apart tidally) slows and asymptotically approaches the event horizon, which over a very long but finite time shrinks until it vanishes.
From the perspective of the infalling observer, (which has been torn into subatomic particles and radiation by the tidal forces), it seems to cross the event horizon without delay -- except that there is no event horizon any more. During the short trip, the black hole has evaporated, and all the particles which had at one time or another been gravitationally captured outside the event horizon will be now "emitted" where the hole has just ceased to exist (but billions of years later from the perspective of outside observers).
Asymptotic Black Holes (Score:3)
Physicists... (Score:1)
--
" It's a ligne Maginot [maginot.org]-in-the-sky "
It will glow nice (Score:1)
C = speed of light.
Bad link (Score:1)
Re:Well... (Score:1)
Re:Velocity is relative (Score:1)
Special Relativity.
Re:In a Brick (Score:2)
Re:Hmm (Score:1)
As for the comment about centrifugal force, if the fluid were (say) contained inside a closed cylinder, which it nearly filled, it would have nowhere to go, and so, no way to break up. (Although that may not be a problem anyway, if the dielectric constant is sufficiently high; they mention materials which reduce the speed of light down to a few metres per second...)
Cheers,
Tim
Re:In a Brick (Score:2)
No, that is not possible; conservation of energy expressly forbids such a thing from happening. In this case, as in all others, the energy is simply converted to some other form.
As for a brick being the same thing, that is also incorrect. The difference is that even the brick reflects light, otherwise you would be unable to see it. A black hole, however, not only does not reflect any light at all, it actually "sucks in" light that strays too close. In the case of the "fluidic black hole", presumably any light that strays too close to the vortex will similarly be sucked in.
Cheers,
Tim
Re:Maintaining Liquidity (Score:3)
Re:Velocity is relative (Score:1)
The velocity of light in a vacuum is constant. Most of the time, the speed of light in an object is usually only fractionally smaller than the speed of light in a vacuum, and as a reuslt the difference is usually ignored to simplify things for the person doing the mathematical calculations (physics classes, for instance).
However, there are certain exotic materials and methods that can be used to slow the speed of light down drastically. This would be one application of those materials/methods.
Re:Asymptotic Black Holes (Score:1)
From the Article:
"Since light in an optical black hole would behave analogously to matter in a real black hole, these light-trapping whirlpools would permit laboratory study of Hawking radiation, the hypothetical emissions from evaporating black holes; this radiation, which consists of particles made near the hole's boundary, is next-to-impossible to observe directly since it is obscured by the cosmic microwave background."
The article also mentions that they are using condensates, the same stuff that slows the speed of light to around 38 miles per hour (to an outside observer). Now, since c is a constant, that means that the conditions in the condensate are either such that 1) distance has increased, or 2) time has slowed down. So, it probably does slow time down as well.
-- /. would be eliminated".
Evan "If people would read the articles, 75% of the content on
Re:Paradox? (Score:2)
Light is *not* a constant speed, it is only a constant for a given energy density of space.
When light travels through air, or water, it slows down (albeit not by much).
I Think the theory goes that if you make it pass through a gas with a very high density.. it slows down even more.. and a BEC (Bose-Einstein Condensate) I believe can be used to create a gas or other transparent material with a very high energy density (BEC, if I recall, is basically a whole bunch of atomic nuclei stuck together acting like one large atom.. something like that).
If this density is high enough, and the material is trasparent, in theory the speed of light throug the material could be slowed extremely.
You are right, though.. they will make a whirlpool spinning at near light speed because they have slowed the speed of light
do you think... (Score:1)
Try this... (Score:1)
Tah dah!!! you made yourself a nice lightsabre!!!
Moderate this one up!!! (Score:1)
A million household uses! (Score:1)
Need some peace and quiet? Try our new Portable Model NahNahNahICan'tHearYou(tm). Used like a normal Walkman(tm), this portable version of the ABH frees you up from all those irritating sound waves you didn't want to hear! Relax and read the paper while standing next to a jet engine! Experience the complete peace of space without the millions of dollars in training needed to get there! Selectively eliminate the sounds of barking dogs, crying children, nagging spouses, co-worker PC startup WAVs and more!
If you live near an airport, why not ask for a free demonstration of our mid-size Dead Quiet(tm)- suitable for all single-story residences. Eliminate those pesky sound waves from passing jets and imagine you're at the quiet country house you couldn't afford in the first place!
* It is not advisable to operate the NahNahNahICan'tHearYou(tm) Portable Personal Accoustical Black Hole while operating machinery or driving. ABH Technologies Limited does not endorse standing next to jet engines during operation. Example used for illustrative purposes only.
Re:Maintaining Liquidity (Score:1)
"a Bose-Einstein condensate or a rubidium gas"
-NF
Hawking Radiation. (Score:2)
Hawking radiation originates in the background of virtual particles in the universe -- particles that appear spontaneously from nothing along with their antiparticles, then collide and exterminate themselves. This background energy is a vital part of our models of the universe.
Stephen Hawking theorized that near a black hole some these virtual particles would be sucked into the black hole while their antiparticles would remain free. Thus, some virtual particles become permanent and real particles, and the black hole effectively radiates them into space. Conservation of mass states that the black hole must then be shrinking slowly in size...but that's not important here, with the laboratory optical black hole.
The optical black hole will have the same effect as a real one; virtual particles will be trapped within it, and their antiparticles will fly free. (Note that the trapped particles may be either matter or antimatter -- the radiated particles will be the opposite of the ones trapped.) Scientists will then be able to measure this Hawking Radiation and test some very central theories of cosmology and quantum physics.
Theoretically (and there's a point at which the theory is so remote, it's only fantasy...but here goes), an optical black hole *might* be configured to collect the radiated antiparticles as a bose condensate themselves. Then the optical black hole serves a purpose -- it's an antimatter generator. But that's really, really far beyond what they're trying to do now.
...
Remus Shepherd
Yes, I am a physicist. Yes, I do play one on Usenet.
Re:Transparency (Score:1)
Re:Paradox? (Score:2)
This is not quite correct. The speed of light in a dielectric depends on the index of refraction, n, of the medium; n is in turn a function of the magnetic permeability, mu, and dielectric constant, epsilon of the material. At the root of it all mu and epsilon are functions of the molecular and electronic structure of the medium, as well as the frequency of the light itself. Thus, two materials with similar densities but very different dielectric constants will have very different indices of refraction, and hence light will propogate within them at different speeds. What's more, even for a single material, n (and hence the speed of light) will in general vary with wavelength. This is called "dispersion", and it is responsible for such diverse phenomena as rainbows, prisms, and smearing of pulses from pulsars.
The important thing to remember is that only the speed of light in vacuo functions as an absolute "speed limit". Particles can and do exceed the speeds of light in dielectric media, causing them to emit Cerenkov radiation in the process.
-r
Re:Authors hung up on "not even light can escape" (Score:2)
-r
Re:Transparency (Score:2)
Imagine you have a lump of some material. The electrons circling the atoms or molecules of the material have some characteristic structure that depends on the elements involved, how the electrons are shared in any molecular bonds in the material, and how the atoms or molecules are arranged in the bulk material (proximity of other atoms or molecules distorts the energy levels for orbiting electrons). This latter factor, by the way, is the difference between coal and diamond.
Now, along comes an electromagnetic wave, which is really just an electric field oscillating with a magnetic field. The electrons in the material are going to feel a force due to the E field (in this naive treatment we'll ignore the magnetic field). What's more, that force will want to drive the electrons to oscillate, but those oscillations will be resisted by forces that depend on the factors I mentioned above. The punchline is that the more the electrons are free to respond to the electric field's driving force, the more energy they will dissipate, the more the incoming light will be attenuated, and hence the more opaque the material will appear. Conversely, if the electrons are not free to respond, the light is not attenuated (much) and the material appears transparent. As you might expect, for any given material the response of the electrons varies greatly with frequency (just like the case of mechanical resonators). This gives rise to all sorts of phenomena, which you can find described in any good optics text.
Now, in the case of conductors (like metals) the electrons are very free to move around (that's what gives them their conductivity), and hence you would expect them to quickly dissipate any electromagnetic waves incident on them, and that is generally the case. Typically the ``skin depth'' for metals is about 1/6 of a wavelength. However, as you go to higher frequency, things get complicated again, because the conductivity has a wavelength dependence. Generally that dependence takes the form of a strong drop off in conductivity above some characteristic frequency. Evidently, this characteristic frequency is well above visible light frequencies for naturally occurring metals.
Another poster mentioned that DARPA is working on transparent metals. Presumably, then, their line of attack is to try to find some alloy with a crystalline structure that makes that alloy's characteristic frequency lower than visible light frequencies. If and when they succeed, it will be interesting to see what that does to the metal's other characteristics like malleability and ductility.
Hope that helps (and I hope I didn't post it too late for you to get back around to reading it at some point).
-r
Re:Hawking Radiation. (Score:3)
I am skeptical that these "optical black holes" will trap particles as well as they trap light. Particles have no problem traveling faster than the speed of light within the dielectric, so long as they do not exceed the speed of light in vacuo. Thus, particles should be able to escape these things, even if light cannot. In other words, these beasts have no true event horizon, and so any analogy to astrophysical black holes is suspect.
Robert Link
Also a physicist. Gave up on Usenet a long time ago.
Authors hung up on "not even light can escape" (Score:4)
What's more, from the standpoint of General Relativity these constructs don't look anything like a black hole. The stress-energy tensor (the relativistic analog of mass density) is virtually unchanged by the modest rotational flows light traps made from Bose-Einstein condensate would require, meaning that these constructs should have exactly the gravitational properties you would expect of a static body of liquid in the laboratory (i.e. none to speak of). That means no space-time curvature, no ergosphere or frame dragging, no gravitational redshift, and no time dilation. For example, if they directed a stream of muons through these things they should find the muons' decay lifetime basically unchanged from what it would be if they sent the muons through the same liquid while it wasn't rotating.
I believe the authors make an important mistake when they say "... a moving dielectric medium acts on light as an effective gravitational field." That is clearly not true because this putative "gravitational field" does not obey the equivalence principle; viz. it accelerates light but not matter. The mistake is comparable to saying, "A charged pith ball in an accelerating train car will experience an `effective electric field' which will tend to accelerate it." and proceeding to compute the electromagnetic properties of this moving field. The analogy falls flat because the acceleration is not caused by an electric field, and so it can't be expected to act like one when you study its influence on anything else in the train car. Similarly, although you can compute a gravitational field that would trap light in the same way as these constructs, that doesn't mean that there is actually a gravitational field present, nor does it mean that other effects that would be present for the gravitational field you calculated will actually show up in your apparatus.
None of that means that this isn't interesting research, of course, but as far as I can tell the connection to black holes and astrophysics is nonexistent.
-r
Re:This is why Science is dangerous. (Score:1)
You wouldn't be worrying about this anyway, because a 1g black hole would rapidly release rather a lot of energy as it evaporates (E=mc^2...), so you'd probably have some rather more exciting problems to work on... (Like how to reattach severed limbs)
Andrwe.
Re:Well... (Score:1)
uhm, ok, let us review significant figures. You just quoted a number to six decimal places, or one part in 400,000, but prefixed it with the word "about."
It occurs to me that you could be using "." to mean "," but if you want me to accept that, you had better use the correct abbrviation for kilometer, which is km, not KM (Kelvin Mega?).
As others have said, you also oughta be more precise when you talk about light speed in an opaque medium.
Re:Imagine.... (Score:2)
Any culture that cannot laugh at itself does not deserve to exist.
Re:Well... (Score:2)
Re:This is why Science is dangerous. (Score:2)
On the other hand, I am basing this on almost no information. Can anyone point us to a well thought out mathematical model of this?
Re:This is why Science is dangerous. (Score:2)
However, there is a large difference between a 1g block of steel and a 1g black hole if you are trying to keep it sitting on a table [or in any other non-vacuum]. The steel and the hole will have the same gravitational effect if you are 2cm away from the center of each, but anything very close to the hole WILL get sucked in, because the gravity DOES make the escape velocity rise to above the speed of light as you move towards it. If you "set" your 1g black hole down on the table, it would not and could not be supported and would fall straight thru any matter in its way until it got to the center of the earth. As it went and once it was there, it most definitly continue to suck matter in. Perhaps the rate of suck would be very small at first, since particles have to get real close in order to be trapped, but the more that it eats, the more it sucks.
On the other hand: A 1g black hole would evaporate (read: explode) very quickly due to hawking radiation.
And: They are not making black holes anyway, that is just an analogy, RTFArticle.
Re:This is why Science is dangerous. (Score:2)
At some point I will do the math for [1g black hole versus density of particles it will encounter] and [time it takes to explode due to hawking radiation], but right now I am too overworked already.
Re:This is why Science is dangerous. (Score:1)
> would instanty be consumed by the hole itself; > or rather the matter entering the hole > (electrons being a component of matter but
> inexistent without it)
But that's exactly the point... electric charge is always conserved. If electrically charged matter enters a black hole, the black hole must now have electric charge.
An even better way to charge a black hole would be simply to set up a bunch of electron guns, and shoot at the hole for a while. Eventually it'll get a charge, at which point some magnets would be just fine in moving it. True, it'd have a huge inertia, but it'd move.
In general, true black holes (not these optical ones) have 3 properties:
1) Mass
2) Charge
3) Angular momentum. (i.e. spin)
All other information disappears.
Thus the saying, "black holes have no hair"
Reducing Manufacturing Costs (Score:1)
Today, they build the dam thing in a Lab. Next week, you will be able to buy one of them for a couple thousand bucks at ebay. Them they hit the shelves at Amazon and other places...
In a year or so they will be comming free with your favorite breakfast cereal...
Hmmm...I think that not even Galactus would have dreant of that. Should make a nice sauce to go with planets.
Of course they had already had the technology to do this on the past [slashdot.org], but it seens they had improved something on security since.
Re:Destruction of the Universe Possible? (Score:1)
Re:Try this... (Score:1)
hold the vortext a certain distance from the laser
handle, that way you wouldn't have to worry about
the stick getting caught on something if the
laser didn't cut fast enough
How much light can that thing hold? (Score:1)
--
not permanent! (Score:1)
Where is my mind?
Re:Scares the hell out of me! (Score:3)
The whole experiment is about as dangerous as playing with a laser pointer.
Re:Asymptotic Black Holes (Score:1)
There would, however, be a localized time dilation effect in a vortex medium that was moving at near-c velocities.
who the hell do you think? (Score:1)
Well... (Score:1)
At last ! (Score:1)
Bad Coriolis (Score:1)
Unfortunatly this opinion is backed up by other sources: Bad Coriolis [psu.edu]
And for the Simpsons fans out there...[2F13] Bart vs. Australia [snpp.com]
There are other sources - check Google [google.com]. Of course there are probably sites out there that encourage the myth, but that's the nature of myths.
Re:Bad Coriolis (bad website) (Score:1)
From the 2nd link, it refers to the sci.physics FAQ - which I hope would be a reputable source of information: Which Way Will my Bathtub Drain? [ucr.edu]
wrt your comment on the author of the first site, I'm inclined to agree.
Blackdot (Score:1)
Re:This is why Science is dangerous. (Score:1)
Black holes can be electrically charged, and can therefore be moved using magnetic fields.
black holes would be cool (Score:1)
some references (Score:2)
Optical Black Holes reference:
U. Leonhard and P. Piwnicki, Physical Review Letters, 84, 822-825(2000).
This is the actual reference to the paper proposing optical black holes. It has been published in what is arguably the most respected physics journal(not some speculative rag). Many of you are asking about a material in which the speed of light is very slow. Such a material was demonstrated last year:
L. V. Hau, S. E. Harris, Z. Dutton, and C. H. Behroozi, Nature(London) 397, 594(1999).
In this paper Hau et. al. demonstrated that light traveling through a Bose Einstein Condensate is slowed to a mere 17 m/s. This is slower than most bicycles ride(as illustrated by the cover of that weeks nature). To find out what Bose Einstein Condensate is you can refer to:
Anderson, M. H., Ensher, J. R., Matthews, M. R., Wieman, C. E. & Cornell, E. A. Observation of Bose-Einstein condensation in a dilute atomic vapor. Science 269, 198-201 (1995).
Now go to your local University Physics Library and look a few of these things up before advertising your ignorance and pronouncing that this is bullshit just cause you read some bullshit article on real science
Read the article... (Score:1)
Read the article... (Score:1)
that it's not a real black that will be
created but something that will have
similar behaviour...
Jeez,...
its those scientist you seem to distrust
so much that've told you all they suppose
about black holes. They're the ones who
make back of the envelope estimates. Yet
you think you (clearly someone who gets all
his knowledge from SF-comic books or movies)
understand the dangers better than they do,...
oh puh-lease,
If you know nothing, understand nothing
and have no clue whatsoever what you are
talking about just shut up will you...
(Oh yeah, real (wo)men post their name)
J.
P.S. sorry messed up lay-out last time
This just in... (Score:1)
"We are very exited by this" says a spokesman for the Unmoving Picture Association "Maybe it is possible to create a device so that information cannot escape its proximities, or at least bend over"
Optical Black Hole in a medium...Hmmmm (Score:1)
Scares the hell out of me! (Score:1)
Re:Destruction of the Universe Possible? (Score:1)
Just through enough storage at it, and it won't ever swap. 640 kilophotons should be enough for anyone.
Re:Destruction of the Universe Possible? (Score:2)
Of course, users of modern universes will gleefully point out that, in theirs, light rarely actually swaps -- it pages using an LRU algorithm.
Destruction of the Universe Possible? (Score:3)
Then it sounds like this experiment, modified, could result in the instantaneous destruction of the universe:
First, get the light within the artificial vortex to slow down.
Then, place the device containing the experiment within a good-quality vaccuum, like an Electrolux (or an old VAX).
At that point, the light within the experimental device has a problem -- it's supposed to go the speed of light 'cause it's in a vaccuum, but it's supposed to go slower because it's going through some other materials.
The result of this contradiction might be the immediate destruction of the entire universe, followed by some quick behind-the-scenes fixing of microcode bugs and a reboot. (This sort of crash is known by the heavenly hackers as a "BSOD", or "Black Suck of Death".)
(Or, we might just learn which if these "laws" is wrong!)
/. Black Hole (Score:1)
How do we do this?
Re:In a Brick (Score:1)
A black hole (in the sense of a gravitational black hole) actually destroys the photons etc. as they enter it. A box simple stops the light getting to your eyes. The light is still in that box, and it would eventually be converted into other energy forms (I.E heat).
Re:In a Brick (Score:1)
Re:Well... (Score:2)
Another approach... (Score:1)
Regards,
Create a BH in your basement... (Score:1)
Re:Well... (Score:2)
How exactly do you make light go slower?
One method of making light go slower is to use a window. Light travles at approx 200,000 km/s in glass, compared with almost 300,000 km/s in air.
The speed of light is not constant. The speed of light in a vacuum is constant. The speed of light in a Bose-Einstien Condensate (which is what these folks are planning to use) is far far slower than the speed of light in glass or in air or in a vacuum.
Optical Black holes are *not* Gravity Wells (Score:1)
Re:This is why Science is dangerous. (Score:1)
A black hole will contain you before you can contain it
Re:This is why Science is dangerous. (Score:1)
No,but seriously, even if you could create a conductive core which could touch a black hole (precisely on the event horizon) any electricity would instanty be consumed by the hole itself; or rather the matter entering the hole (electrons being a component of matter but inexistent without it)
I however do know of one plausible way of moving (not containing) a very small black hole: you can 'tow' an object of simmilar mass infront of you black hole and the black hole will be constantly attracted to your object, and so long as your object doesn't approach the event horizon you are safe - quite how you re orient yourself to stop your 'hole' is another matter
The major problem with moving a hole this way is a - there is no scientific proof or disproof that an 'event' can exist in any other place other than where it begins.
b - the energy needed to pull your 'equally massive object' would somewhere in the order of 10_-100,000,000,000Nm
As for how much matter you would need to create a charge high enough to charge the event horizon; every particle in the universe might be a good start.
And if you could use an electronic field to attract a hole, your still left with the same problem of how to generate enough energy to move your cosmic 'tow' vehicle.
The bottom line is that a gravity well at critical mass (a black hole) the size of a teacup would have roughly equal mass to 1 sun: if it oversteps critical mass, you haven't got enough fingers & toes to count the relative mass....
Re:This is why Science is dangerous. (Score:1)
Re:Paradox? (Score:1)
Paradox? (Score:2)
Here goes: They use the word 'comparable' when it may have been better to use 'relative'.
The gist of it is you can't accelerate matter up to the speed of light; therefore you slow the light down instead. So you don't need a whirlpool which spins at hundreds of thousands of miles
per hour
It would be interesting to see if some of Steven Hawkings theory is correct, and if you haven't read the 'brief history of time' go out and buy now! (but not from amazon.com) its worth it just to have on the coffee table when friends are round
(friend:"ooh, whats that book about" you:"well....")
Maybe you all understood better than I, just thought I would post this incase anyone was left scratching their head.....
Re:This is why Science is dangerous. (Score:3)
Actually, no we aren't. Not in the important sense of a gravitational singularity. This is merely something that simulates some aspects of a black hole, namely that light goes in and doesn't come out. Theory suggests that this violates preservation of information, meaning that there must be some other force at work countering it. That's the radiation part. To examine this would be an interesting insight into a realm we don't know much about.
But this is not a dangerous experiment in any way. Your armageddon scenario fails because there isn't any actual singularity in the picture.
-- Eythain
PS Besides, the 30 minutes calculation for a real balck hole is way off, or rather, that would depend entirely on the mass of the black hole in question. A natural black hole from a collapsed neutron star would squish us before we even got close, whereas a quantum black hole we could concievably make would probably be so small it would evaporate, or even if it wasn't, it would not significantly affect the Earth (I mean, it's not likely we can make a black hole a significant fraction the mass of Earth, where would that mass come from?) while growing. Since a singularity this small is basically point sized (even the event horizon), it would be severely limited in how quickly it could swallow matter. So relax, we'd certainly have a century or so to evacuate, even in the worst case scenario.
A good book on that horror scenario would be Earth, by David Brin.
Re:some references (Score:1)
Many of you are asking about a material in which the speed of light is very slow. Such a material was demonstrated last year:
Yeah, but accelerating it in any manner is going to add plenty of energy so that light moves much faster.
Re:Maintaining Liquidity (Score:1)
If this were the speed of light in a particular medium, then it wouldn't take too much to make the medium go faster than that.
Er, yeah, but if you try to move the medium, you're going to add plenty of energy, and then you'll no longer have a Bose-Einstein condensate. I can't see how you'd be able to do this without finding a different material capable of slowing the light down.
Re:Maintaining Liquidity (Score:1)
If you recall the story ran here a while back, researchers have been able to slow down the speed of light to just a few meters/second. Using this technique, it would be possible to create a vortex that would be able to trap this slow moving light. Therefore, it is not necessary to speed up the vortex by millions of miles an hour - just fast enough to trap the slow moving light.
Re:This is why Science is dangerous. (Score:1)
Seems some of us are forgetting our high school physics.
--Kevryn
La Comode' (Score:1)
After all, who wants to see that water anyway? ;)
Already Been Done. (Score:1)
In the meantime, physicists are also pursuing the idea of creating "acoustical black holes" (dumb holes),
It's already been done: Courtney Love and her band.
Re:Well... (Score:1)
-Elendale (err... I have nothing witty to say here)
This is an old party trick ...... (Score:1)
Neat stuff (Score:1)
Re:Well... (Score:1)
Re:This is why Science is dangerous. (Score:1)
Re:Well... (but not a gravity one) (Score:2)
A medium? That sounds more like sorcery than science. Is it done with crystals?
I think that if science can invent air brakes (presumably to help us brake wind), then why not invent light brakes to slow their light down? This is different than brake lights which are just an indicator (usually of the speed of traffic, not light).
Also, if they slow the light down, wouldn't it only be an optical brown hole? And since it's not a real black hole (or brown), but only an optical one, what's to prevent people from checking it out and saying, "I just don't see it"?
In a Brick (Score:2)
Else I just made a black hole by lighting a cylume stick inside a brick, or putting a flashlight in a draw an closing it. Or drawing the blinds.
Rotating fluid faster than the speed of light within it is like putting a brick on the table and saying that it's going faster than the speed of light within it. Or sitting stock still in a vacuum and saying you're going faster than the speed of sound.