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Antimatter experiment produces first beam of antihydrogen
- deleted 13y ago[deleted]
- blisterpeanuts 13y agoMuch more informative than that Slashdot summary and the horrific comments that follow.
- ChuckMcM 13y agoThe lack of antimatter is an enduring mystery. And creating it is always cool. And I find it particularly fun to imagine anti-matter fusion plants producing anti-helium (more bang for your buck antimatter :-).
- HCIdivision17 13y agoIt thrills me that the Antiproton Decelerator is a legitimate thing that is at least as cool as it sounds. The need to slow particles down is obvious only in retrospect for me,which I'm a little ashamed to admit. Add, too, that the acronyms are excellent. [0] http://en.wikipedia.org/wiki/Antiproton_Decelerator http://en.wikipedia.org/wiki/Antiproton_Decelerator
- TrainedMonkey 13y agoHigh energy physics is one of the leading fields that drives scientific progress forward. Studying antimatter is particularly cool, because at the face value it is one of the most efficient ways to store energy (Basically 100% of matter gets converted to energy). Now if only we could figure out a way to cheaply produce it without relying on fossil fuels.
- leeoniya 13y agoProxima Centauri holds extremely high promise for human exploration. If we could only get there. Curing cancer will revolutionize human health. If we could only cure cancer. and so forth...
- TallGuyShort 13y agoHis comment is a little more meaningful and less redundant than that. For instance, I was aware of the difficulties in storing anti-matter, but it hadn't occurred to me why it would be such an efficient energy storage mechanism. Sure we can't store it well yet, but obviously that's one of the things scientists are going to be thinking about the most as they look to do more experiments with.
- gus_massa 13y agoEven if it were easy to produce, the problem is where to store it.
- HCIdivision17 13y agoWhy, you use ATRAP, of course! [0] http://en.m.wikipedia.org/wiki/Antiproton_Decelerator#ATRAP http://en.m.wikipedia.org/wiki/Antiproton_Decelerator#ATRAP
- angersock 13y agoWhat have been the useful benefits of this research? I don't see any obvious examples--does it help things like smaller fabrication for chips? EDIT: Folks, I'm not being a jerk here. For example, a lot of the engineering that went into missles and the space program (integrated circuits, GPS, etc.) has application elsewhere. Fundamental science research into materials and electromagnetics has given us wifi, radio, and television. Research into x-rays and radioactivity gave us medical x-rays and radiotagging of isotopes for understanding reactions. High-energy physics research seems to have no immediate or even long-term application beyond satisfying "How does this stuff hold together?"--my question about chip fabrication was specifically in regards to the idea that things like advanced lithography techniques probably are advanced by this research. The parent made this claim: High energy physics is one of the leading fields that drives scientific progress forward. I am simply asking this assertion to be justified and elaborated upon for those of us unfamiliar with those impacts.
- Crito 13y agohttp://phys.org/news/2012-07-particle-physics-.html http://phys.org/news/2012-07-particle-physics-.html Edit: Or to be more direct, and therefore less helpful, "scientific progress" is not a measure of "things that are useful to me". Scientific progress can, and historically is, made when we expand our knowledge of the world, not exclusively when we find practical applications of that knowledge.
- angersock 13y agoSo, no, it does not "drive science forward"--it may, one day, lead to more interesting questions. There's nothing wrong with that, but acting like it is generating ROI today--or has in the past--is disingenuous. Without validating your assertions or disclaiming them properly you are perpetuating the sort of nastiness science is supposed to fix. EDIT: Your addition about "drive science forward" as opposed to "drive engineering forward" is a subtlety that is worth repeating.
- rosser 13y agoSo, no, it does not "drive science forward"--it may, one day, lead to more interesting questions. Leading to more interesting questions is, in fact, a significant part of "driv[ing] science forward".
- Florin_Andrei 13y ago> Studying antimatter is particularly cool, because at the face value it is one of the most efficient ways to store energy (Basically 100% of matter gets converted to energy). In theory, a black hole is also a 100%-efficient converter of matter into energy, via the Hawking radiation. A microscopic BH might radiate very large amounts of Hawking radiation. The bonus is that, unlike antimatter, you can make (or at least fatten up) a BH directly from ordinary matter, without spending energy as a prior step (anti-matter is energy storage, a black hole is an energy source - if you're willing to spend some dirt as "fuel"). Of course, the problem of storage is just as bad, if not worse.
- wyager 13y agoI hadn't thought about black holes as an energy source. Cool idea. But where does the energy actually "come from"? With M/AM interactions, the M/AM is annihilated, which creates harvestable photons. Does the energy given off by a black hole come from the change in entropy from structured matter to unstructured Hawking radiation or something? It seems almost too easy if we can just feed any old matter into a black hole and get energy out...
- maxerickson 13y agoIf it is a traditional black hole, it has to have a pretty large mass to have a manageable energy output (they burn faster as they lose mass). On the other side, if it is too large, the energy output is miniscule.
- waps 13y agoThe energy comes from virtual particles. You should think of it this way : anything has a certain chance of happening, but must follow conservation laws. Conservation of energy, conservation of mass, conservation of ... (the "real" conservation laws are more complex, but ... E.g. only mass+energy+entropy is constant, not mass, nor energy, nor entropy). But small, "short term" violations are possible. Now imagine there are particle pairs that, when added together have zero mass, zero energy, zero ... These would pop into existence in pairs everywhere and be anihilated soon after. Same is true for triples, quadruplets, ... with different probabilities. Surprise : these particles "exist" (normally for very short times). So particle a and particle b come into existence, both particles on a path that separates them from eachother. However, because opposite charges attract (and other effects related to other forces) they will fall back into eachother after a while, anihilating eachother and leaving nothing. These are generally referred to as "virtual" particles. Except of course if something comes between them while flying on their path. This results in multiple effects, like the Casimir pressure, and hawking radiation. The Casimir pressure is simpler. Suppose you have 2 straight plates, and you bring them close together. So close that these virtual particles have a good chance of impacting one but not the other. If the plates are metal, the particles will generally "merge" with it (like electrons). So a tiny percentage of the virtual particles between the plates become real. This does not affect virtual particles that are not between the plates. So there is a clear differential between vacuum interactions outside of the plates and inside. This results in a massive pressure pushing the plates together, like removing gas particles in a container results in a pressure on the outside of the container (and, in an athmosphere of large molecules, if you move plates closer together than the size of the gas molecules, there will be a pressure that pushes the plates completely together). Likewise, in black holes what comes between the particles is an event horizon. Event horizons "erase" quantum information, only the black hole as a whole has quantum information (the reason for is that black holes are physical, localized, manifestations of the end of time : they don't have an inside as far as anything outside the black hole can detect), no individual parts of a black hole have quantum state. So if an electron crosses the event horizon the charge of the entire black hole changes instantaneously, and the point charge of the electron disappears. That means the charge pulling the particles back together (assuming an e+ and e- virtual particle pair) becomes much more distant to the particle, and if it has enough speed and a convenient direction it will fly away from the black hole. Due to conservation laws the net result is that the black hole has eaten a somehow negative-mass charged particle, and the mass has decreased. A particle has been created outside of the black hole and is flying away to infinity. The vast majority of these particles are photons of a specific frequency, and, surprisingly, the smaller the black hole, the larger the effect (and the higher the frequencies). So spaceships would have to carry "heavy" black holes to get a decent output and would have to "feed" the black holes to avoid exploding (millions of tonnes as least, and you have to shovel in matter at a rate of 10+ kg per second to keep it stable. Or you could reflect hawking radiation back in). And of course, large black holes have large inertia (plus : how do you hold on to one ? Electrical fields can do it, but it would have to be a field so huge it baffles the imagination ...). A 1kg black hole would be converted into energy in less than a planck second by this effect and there is nothing, even theoretically, that can hold back that energy. Such an explosion might even do what people were "afraid" would happen with CERN's Higgs experiments and disrupt the Higgs field, causing a cascading conversion of the energy "powering" inertia into photons (the higgs field is something like a magnetic field that opposes all velocity changes in mass). If this were to happen, it would look one hell of a lot like a big bang.
- yongjik 13y agoI don't think it works like that. The only known way to make antimatter is to convert energy into matter-antimatter pairs, so basically you need the same 100% of energy to produce antimatter in the first place. (In fact, I think the current physical theory prohibits any kind of matter-antimatter conversion, but I'm not a physicist so I might be wrong.) So, if we had enough energy to make these antimatter, we could simply use the energy directly, without going through the massively inefficient step of funneling that energy into liquid helium and superconducting magnets and city-wide vacuum circles and so on.
- orik 13y agowe could simply use the energy directly, but I think he was talking about storing energy. >most efficient ways to store energy
- yongjik 13y agoWell, maybe he did, but I parsed his phrase in the other way: > ...a way to cheaply produce it without relying on fossil fuels. It sounds like regarding antimatter as a possible alternative to fossil fuels---which it can't be. (It can be an alternative to oil tankers, I guess.)
- xerophtye 13y agoTechnically, all forms of energy "production" we have are basically extraction from an existing store of said energy. Try reading[0], it's about the two guys who proposed a black hole powered space ship. What they suggest is extraction energy from the sun (an existing source) and making a black hole (or maybe more from the same one), and then use that to power your ship. "With a set of four machines: black hole generator, black hole drive, power plant, and a self perpetuating black hole powered black hole generator, the potential is enormous. " [0]http://io9.com/5391989/a-black-hole-engine-that-could-power-spaceships http://io9.com/5391989/a-black-hole-engine-that-could-power-...
- deleted 13y ago[deleted]
- gus_massa 13y agoThe problem is that to do something useful you don’t need only energy but low entropy. The easy way to calculate it is using the Gibbs free energy http://en.wikipedia.org/wiki/Gibbs_free_energy http://en.wikipedia.org/wiki/Gibbs_free_energy . To produce some work and transform the radiation energy you need also a cooler heat sink to hide the entropy. The black holes are very cold, so you need something cooler. You must have a very tiny black hole with a temperature over the ambient temperature (25°C=77°F), so the heat flush from the black hole to the ambient and you can harvest a part of it as useful energy, for example with a electricity generator.
- jxf 13y agoCan someone explain where the antihydrogen winds up after being created? Is it annihilating with something?
- InclinedPlane 13y agoEven extremely strong vacuums contain large amounts of atoms, and there are the walls of the vacuum chamber, of course. When an anti-hydrogen atom collides with any normal atom an electron will annihilate with the anti-hydrogen's positron leaving behind a negatively charged anti-proton which will fairly rapidly collide with a positively charged proton in a nucleus.
- jxf 13y agoWouldn't colliding with the walls of the chamber be extremely undesirable? That seems like it would create stress/damage in the chamber, and given how sensitive and expensive ALPHA is I'd imagine that they don't want to do that, right?
- InclinedPlane 13y agoIt's not a problem. It's important to keep an understanding of the scales involved here. A gram of Hydrogen contains 6e26 atoms. So a nanogram of material contains on the order of 10^17 atoms. That's ten million trillion atoms. A "beam of antimatter" which literally annihilates the walls of the vacuum chamber it is contained within may seem dramatic but in this case we are talking about mere dozens of anti-atoms. Against walls of solid metal the damage is so minute as to be undetectable with even the finest instruments. Even if the beam were far, far stronger it would still only cause erosion at the scale of picograms per trillion anti-atoms, which isn't much concern.
- Sharlin 13y agoWe must remember we're talking about a few dozens of antiatoms here. The few gamma photons they turn into when annihilating are so utterly insignificant compared to natural background radiation it isn't even funny.
- sytelus 13y agoHere's two cool thing about this experiment: Normal Hydrogen atoms do respond to magnetic field feebly. They feel repulsion while travelling in a field gradient. Anti hydrogen has same property and that's how you keep it away from normal matter. Second, they were able to produce 25 anti-Hydrogen atoms per hour. They measured total 80 of those. A long way from anti-matter weapons :).
- Create 13y ago"How should we make it attractive for them [young people] to spend 5,6,7 years in our field, be satisfied, learn about excitement, but finally be qualified to find other possibilities?" -- H. Schopper The numbers make the problem clear. In 2007, the year before CERN first powered up the LHC, the lab produced 142 master's and Ph.D. theses, according to the lab's document server. Last year it produced 327. (Fermilab chipped in 54.) That abundance seems unlikely to vanish anytime soon, as last year ATLAS had 1000 grad students and CMS had 900. In contrast, the INSPIRE Web site, a database for particle physics, currently lists 124 postdocs worldwide in experimental high-energy physics, the sort of work LHC grads have trained for. Let's not confuse students and fellows with missing staff. [...] Potential missing staff in some areas is a separate issue, and educational programmes are not designed to make up for it. On-the-job learning and training are not separated but dynamically linked together, benefiting to both parties. In my three years of operation, I have unfortunately witnessed cases where CERN duties and educational training became contradictory and even conflicting. http://ombuds.web.cern.ch/blog/2013/06/lets-not-confuse-students-and-fellows-missing-staff http://ombuds.web.cern.ch/blog/2013/06/lets-not-confuse-stud... An unsatisfactory contract policy This will be difficult for LD staff to cope with. Indeed, even while giving complete satisfaction, they have no forward vision about the possibility of pursuing a career http://staff-association.web.cern.ch/content/unsatisfactory-contract-policy http://staff-association.web.cern.ch/content/unsatisfactory-... Pensions which will be applicable to new recruits as of 1 January 2012; the Management and CERN Council adopted without any concertation and decided in June 2011 to adopt very unfavourable mesures for new recruits. http://www.gac-epa.org/History/Bulletins/42-2012-04/Bulletin42-en.html http://www.gac-epa.org/History/Bulletins/42-2012-04/Bulletin... And a warning to non-western members: "The cost [...] has been evaluated, taking into account realistic labor prices in different countries. The total cost is X (with a western equivalent value of Y) [where Y>X] source: LHCb calorimeters : Technical Design Report ISBN: 9290831693 cdsweb.cern.ch/record/494264