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Lab-Made Fireball May Be a Black Hole
MoogMan writes "BBC News reports that a lab fireball may be a black hole.
From the article: "A fireball created in a US particle accelerator has the characteristics of a black hole, a physicist has said. The Brown researcher thinks the particles are disappearing into the fireball's core and reappearing as thermal radiation, just as matter falls into a black hole and comes out as "Hawking" radiation." More information available from the NewScientist article (subscription required)."
The e-print of Nastase's paper.
For Horatiu Nastase's paper in pdf format: Title: The RHIC fireball as a dual black hole
A puzzling signal in RHIC experiments has now been explained by two researchers as evidence for a primordial state of nuclear matteA puzzling signal in RHIC experiments has now been explained by two researchers as evidence for a primordial state of nuclear matter believed to have accompanied a quark-gluon plasma or similarly exotic matter in the early universe. Colliding two beams of gold nuclei at Brookhaven's Relativistic Heavy Ion Collider (RHIC) in New York, physicists have been striving to make the quark-gluon plasma, a primordial soup of matter in which quarks and gluons circulate freely.
However, the collision fireball has been smaller and shorter-lived than expected, according to two RHIC collaborations (STAR and PHENIX) of pions (the lightest form of quark-antiquark pairs) coming out of the fireball. The collaborations employ the Hanbury-Brown-Twiss method, originally used in astronomy to measure the size of stars. In the subatomic equivalent, spatially separated detectors record pairs of pions emerging from the collision to estimate the size of the fireball.
Now an experimentalist and a theorist, both from the University of Washington, John G. Cramer (206-543-9194, cramer@phys.washington.edu) and Gerald A. Miller (206-543-2995, miller@phys.washington.edu), have teamed up for the first time to propose a solution to this puzzle. Reporting independently of the RHIC collaborations, they take into account the fact that the low-energy pions produced inside the fireball act more like waves than classical, billiard-ball-like particles; the pions' relatively long wavelengths tend to overlap with other particles in the crowded fireball environment.
This new quantum-mechanical analysis leads the researchers to conclude that a primordial phenomenon has taken place inside the hot, dense RHIC fireballs. According to Miller and Cramer, the strong force is so powerful that the pions are overcome by the attractive forces exerted by neighboring quarks and anti-quarks. As a result, the pions act as nearly massless particles inside the medium.
Such a situation is believed to have existed shortly after the big bang, when the universe was extremely hot and dense. As the pions work against the attraction to escape RHIC's primordial fireball, they must convert some of their kinetic energy into mass, restoring their lost weight. But the pions' experience in the hot, dense environment leaves its mark: the strong attractive force (and the absorption of some of the pions in the collision) would make the fireball appear reduced in size to the detectors that record the pions. According to Miller, looking at the fireball using pions is like looking through a distorted lens: the pions see the radius as about 7 fermi (fm), about the radius of an ordinary gold nucleus, while the researchers deduce the true radius of the fireball to be about 11.5 fm (Cramer, Miller, Wu and Yoon, Phys Rev Lett, tent. 18 March 2005).r believed to have accompanied a quark-gluon plasma or similarly exotic matter in the early universe. Colliding two beams of gold nuclei at Brookhaven's Relativistic Heavy Ion Collider (RHIC) in New York, physicists have been striving to make the quark-gluon plasma, a primordial soup of matter in which quarks and gluons circulate freely.
However, the collision fireball has been smaller and shorter-lived than expected, according to two RHIC collaborations (STAR and PHENIX) of pions (the lightest form of quark-antiquark pairs) coming out of the fireball. The collaborations employ the Hanbury-Brown-Twiss method, originally used in astronomy to measure the size of stars. In the subatomic equivalent, spatially separated detectors record pairs of pions emerging from the collision to estimate the size of the fireball.
Now an experimentalist and a theorist, both from the University of Washington, John G. Cramer (206-543-9194, cramer@phys.washington.edu) and Gera
When things get complex, multiply by the complex conjugate.
Eh I thought they had worked out that hawking radiation was not matter coming out of the hole, but another part of the accretion disc. Did I pick that up wrong?
Yes, you did. Hawking radiation comes from a black hole's ability to turn virtual particles arising from vacuum fluctuations into a pair of real particles, one of which escapes the black hole's reach. Even in the complete absence of an accreation disc, a black hole will emit Hawking radiation.
of the sub-plot in Thrice Upon A Time
The usual blackholes with at least a solar mass will last incomprehensible amounts of time since a particle formed near the event horizon has to somehow escape the blackhole's gravitational grasp and you have to somehow move the entire black hole's enormous mass in this way. Don't hold your breath.
It's just lazy, confusion notation for 10 x 10^-24 seconds. Who wants to 10 septillionths of a second, anyway?
r s
http://en.wikipedia.org/wiki/Names_of_large_numbe
"The Hole Man" by Larry Niven.
pooptruck
The Brookhaven National Lab located on eastern Long Island, NY gives summer Sunday tours of their facilities(2004 schedule). If you have the chance, then GO! Seeing RHIC up close if pretty damn cool. I'm no particle physicist but their tours are quite impressive and are given by the researchers themselves. Oh, and yes they have beowulf linux clusters too.
Want more ? Here is the Home page-Science Lite for the STAR detector
Please note also that Dr. Nastase was beating these same drums back in 99. I expect that this paper is science politics- at that level you don't want anyone to think you were wrong, so you will spend significant effort at proving your predictions right, despite evidence to the contrary. Oh, and he's not even on the project- he's sucking down other people's results after the fact.
If I understand this correctly, the dual is meant in the sense of the "AdS/CFT-correspondence", which is a mathematical correspondence, or "duality" between a gravitational theory (which may contain black holes) and a "Gauge theory", which is the kind of theory that is used to describe quarks, electrons etc.
The duality means that calculations on black holes may (possibly) be used to understand certain things about this "fireball", but it doesn't mean that the fireball is actually a black hole.
philosopher - when will this stop? You know what would be a good FireFox extension? Automatic spell checker that checks spelling before the page is submitted.
Ok, just found this: SpellBound
You can't handle the truth.
Check out Earth.
I know there are a lot of jokes that can be made about the idea of building a black hole in a lab, but I just want to make sure people understand how not-dangerous a tiny black hole would be:
Black holes do not "suck". Most people -- even most smart people -- have this impression that black holes suck in everything around them with some sort of unstoppable force. This is completely inaccurate.
Black holes only influence things by their gravity. The force a black hole exerts on another object depends on their masses and the distance between them. Exactly the same as the gravitational force between any other two objects, black hole or no.
The part that makes black holes weird is that they can be significantly smaller (as measured by their event horizon) than normal objects. So if you've got an object with the mass of the Sun, normally it's quite large, so the distance between you and its center is big, and the gravity can only get so strong. If you compress that mass into a black hole, though, you can get much, much closer to its center. If you're only a few kilometers away from the center of gravity of something with the Sun's mass, *then* the gravity will be really strong.
When it comes to very small black holes -- especially the type that might be created by a particle accelerator, with masses far less than that of a single atom -- the mass involved is so miniscule that you'd have to get within femtometers or less before the strength of the gravity would even be noticeable.
Now, *if* black holes were indestructible, eternal objects, then yes, even a small one would eventually pick up enough stray neutrinos to start growing, and could eventually become a threat. But, Hawking radiation takes care of that. In fact, the rate of "evaporation" of a black hole *increases* as the black hole shrinks. So micro-black holes would be very short lived, and, again, therefore not a problem.
Here's the wikipedia article on Hawking radiation for reference.
I've read Haldeman's story and it's related, but it's about creating a huge ambitious setup.
...
David Brin's book 'Earth' describes a black hole that 's created at laboratory scale. It's small and innocent and it can't be contained. So it escapes immediately and starts gravitating to the middle of the earth and it grows by sweeping up whatever it passes by. Very slowly at first, but then faster and faster.
This gives a nice touch to the comment in the article that the black hole is harmless
on would almost forget that the guy in the article is perfectly right.
I assumed it was a non-quoted Half-Life reference. The game's silent protagonist, Gordon Freeman, is a scientist who uses a crowbar with satisfying regularity.
Honor Among Slackers. A veri
hawking radiation is described in black hole thermodynamics. a black hole eventually will shrink and disappear due to radiation of particles from inside.
I am the Alpha and the Omega-3
The mass of a black hole doesn't have to be large, if it's a very small black hole. And in certain scenarios, such as those with large extra dimensions, the amount of energy needed to create a microscopic black hole is decreased, basically because gravity becomes comparable in strength to the strong force when you get smaller than the size of the extra dimensions. Hawking radiation from vacuum pair production begins once the black hole is formed.
Nevertheless, that's not really what's being discussed here.. the paper talks about strong-force physics in the collision which is mathematically "dual" in a certain way to the gravitational description of a black hole.
Brookhaven NL, where the RHIC's new black hole lives, indulged in the possibility of creating a "strange" black hole about 6 years ago. 50 miles from NYC. What have they got against us?
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make install -not war
Yes, particles and antiparticles are both created and absorbed in equal proportions. Hawking radiation works because the particle/antiparticle that gets absorbed has negative energy, while the one that is radiated away has positive energy; the one that falls in acquires negative energy because it falls in. See this explanation by gravitational physicist Steve Carlip.
How extremely short lived? From the Wikipedia article you linked.. So, for instance, a 1 second-lived black hole has a mass of 2.28 × 10E5 kg = 2.05 × 10E22 J = 5 × 10E6 megatons of TNT. The initial power is 6.84 × 10E21 W. In the experiement those holes the create must have lifetimes on the order of fractions of a femtosecond as the mass they are using is on the scale of atomic particles which is a whole lot less tha 10E5 kg. Not to mention the decay energy they give up would be awesome. Hmmm.. Step 1 : Create black holes in Lab Step 2: Take the decay energy, convert to electricity Step 3: PROFIT! :)
When RHIC was announced, some in the scientific community expressed concern that it could do just this. The RHIC public relations crew came out and laughed off the concerns as bogus.
Specifically, they said that black holes simply cannot be created whatsoever as there just isn't enough matter or energy for this to happen. The full committee report debunking any such black hole nonsense can be found here.
So now that it has been demonstrated that RHIC's scientists were completely wrong, we're supposed to have further confidence in them how? That the accidental black hole didn't cause the earth to disappear isn't quite sufficient for an answer.
Black holes actually evaporate through the Hawking radiation: the smaller they are, the faster they evaporate. Only black holes large enough to not go POOF! in a nanosecond can survive by eating matter fast enough to counterbalance the Hawking radiation.
Apparently, someone did the math and it takes a black hole as massive as a mountain, or something like that, to not disappear. Until we can create black holes that large from the very beginning i'd say we're safe.
Feasibility rating: 2/10. Highly, highly unlikely. But not impossible.
I really hope that this is just a joke, as there are so many things wrong with this plan, that it makes my head hurt. The feasability is about 0/10. Black holes don't have infinite gravity. The mass of a hole is the same as the mass before it collapsed. So, if you collapse a baseball into a black hole, you have a black hole that weighs the same as a baseball. THE PROBLEM is that it would create an event horizon so small that it would probably pass between all the particles between the surface and the center of the earth. (atoms are mostly empty space, when not being compressed by the immense gravity of say, a neutron star.) Once you have created it, it still only has the gravitational potential of a baseball. Not very menacing.
So, you make a bigger black hole. The energy or mass you need to create a noticable black hole is probably going to be enough, that it could be better used to simply vaporize the earth.
Nice try, though.
HA! I just wasted some of your bandwidth with a frivolous sig!
I so succeeded it, didn't i? ^_^
Man is a slave because freedom is difficult, whereas slavery is easy.
I believe it was in "A Brief History Of Time" I read that a black hole with the mass of a mountain would emit hawking radiation equivalent to 1000 times humanities combined power output.
Therefore, you could not artificially create one without having many times humanities power output, as you would have to cram whatever matter you wanted to put into the black hole against the force of all that hawking radiation.
So I think the earth is safe from these mad scientists. For now.
Forget the New Scientist article, read the actual paper.
Check your chemistry. Since NO and NO2 and N2O5 formation is endothermic, nitrogen in air will not ignite regardless of the temperature - and this fact was well known in 1942-5.
What was not known was the actual temperature and compression required for starting fusion of (light) nuclei like hydrogen and nitrogen. Possibility of hydrogen fusion was investicated since the start of the project. And since nitrogen fusion was presumed to operate in some stars, the remote possibility of igniting fusion in earth atmosphere by fusion bomb was floated at one time. Bethe did some quick math to explain why this was unlikely and re-confirmed it later with more rigorous paper. But the idea of seting air on fire got out and made some non-technical people in government worried.
I doubt that we will ever figure out - and I suspect that even if we did figure out we couldn't do much about it
> At these energies and distances, gravity is not
> the dominant force in a black hole.
Where do they _find_ these people?
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
Apparently this is not a black hole, merely an object that exhibits some black-hole like properties. However, so far as I know, the formation of a black hole depends only on the volume to mass ratio being small enough. I assume that as one pushes matter together, even on the subatomic scale, there comes at point where the gravitational force will become dominant. Certainly this Black Hold FAQ answer seems to indicate that subatomic black holes are theoretically possible.
:)
You are also correct to assume that Hawking Radiation does not happen in a true vacuum, i.e. a piece of space devoid of mass and energy. However, quantum physics suggests that there is no such thing as a true vacuum; on the subatomic scale, the fabric of space froths. Particle/anti-particle pairs are created from nothing. These virtual particles zip apart, then are pulled back together again and annihilate themselves. The total mass/energy gained through these interactions always remains at zero.
However, in my rough, layman's grasp of Hawking Radiation, this changes near the event horizon of a black hole. If one of a virtual particle pair crosses the event horizon, and the other does not, then a curious thing happens (at this point, my understanding of the process breaks down quite a bit). As far as I know, the virtual particles are created in a sort of quantum flux; because they haven't been observed, the particles have not 'decided' which of them is to be the anti-particle, and which is to be made of normal matter. The act of falling into a Black Hole makes a virtual particle into an anti-particle, and thus, the virtual particle outside the black hole becomes a piece of normal matter.
The overall effect is that a black hole gives off radiation, and shrinks due to small particles of antimatter passing through the event horizon.
Note that IANAP, and thus I am probably mostly wrong
Not true. Read up on "Hawking radiation". Hawking theorized that virtual particle pairs created by tidal forces (which normally recombine for zero net result) would sometimes be split by one falling into the event horizon and the other proceeding into the outside universe. Since tidal forces become exponentially stronger the smaller a black hole is, so does the Hawking radiation. Since mass is conserved in this process, to an outside observer it appears as though the black hole is radiating energy and shrinking. Very small black holes shrink much faster than they can pull in Earth-density mass (small event horizon and total gravity), so such a black hole would simply explode rather than growing. This explosion is expected to be quite large by our standards, by the way.
(Hence, if the sun randomly imploded to a black hole, nothing would get sucked in - it'd just be a helluva lot colder and darker)
True, except the potential energy of the Sun's mass in it's current configuration would likely cause a highly energetic event as the mass was sucked into a black hole with a few kilometer event horizon. BTW, I assume you know that a star smaller than 1.4 solar masses can't naturally form a black hole.
Incidentally, 10 million, billion, billionths of a second sounds to me like 10 million seconds...
Much simpler to write it as 1.0e-24 secs.
Galileo: "The Earth revolves around the Sun!"
Score: -1 100% Flamebait
a neutron star with the density of Sol would be roughly the size of a baseball
A neutron star with the density of Sol would not be a neutron star.
All it takes is nukes and nerves.
"Artifact" by Gregory Benford