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LHC Scientists Create and Capture Antimatter 269

Velcroman1 writes "Scientists at the Large Hadron Collider have created antimatter in the form of antihydrogen, demonstrating how it's possible to capture and release it. The development could help researchers devise laboratory experiments to learn more about this strange substance, which mostly disappeared from the universe shortly after the Big Bang 14 billion years ago. Trapping any form of antimatter is difficult, because as soon as it meets normal matter — the stuff Earth and everything on it is made out of — the two annihilate each other in powerful explosions. 'We are getting close to the point at which we can do some classes of experiments on the properties of antihydrogen,' said Joel Fajans, a University of California, Berkeley professor of physics, and LBNL faculty scientist. 'Since no one has been able to make these types of measurements on antimatter atoms at all, it's a good start.'"
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LHC Scientists Create and Capture Antimatter

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  • by bluefoxlucid ( 723572 ) on Wednesday November 17, 2010 @04:54PM (#34260228) Homepage Journal

    The core is negative/neutral mass and the orbit is positive mass. Naturally, anti-matter electrical conductors conduct positive particles rather than negative. The questions of behavior that need to be answered is what exactly causes i.e. electroconductivity. Reversing the charges, in theory, won't affect the behavior insomuch as you have X mobile particles and Y non-mobile particles setting up orbits that should be the same (the nature of electrical charge attraction doesn't change), so anti-copper should conduct positrons like copper conducts electrons etc. The reality... we don't know, of course.

    It would be a big thing if someone created anti-copper AND it didn't behave exactly like copper when supplied with an anti-potential from an anti-battery.

  • by sznupi ( 719324 ) on Wednesday November 17, 2010 @05:16PM (#34260560) Homepage

    First, most of the energy released in matter-antimatter annihilation is carried away by neutrinos.

    Secondly...CERN covered this [web.cern.ch] on one occasion:

    The inefficiency of antimatter production is enormous: you get only a tenth of a billion (10-10) of the invested energy back. If we could assemble all the antimatter we've ever made at CERN and annihilate it with matter, we would have enough energy to light a single electric light bulb for a few minutes. ...

    Can we make antimatter bombs?

    No. It would take billions of years to produce enough antimatter for a bomb having the same destructiveness as ‘typical’ hydrogen bombs, of which there exist more than ten thousand already.

    Sociological note: scientists realized that the atom bomb was a real possibility many years before one was actually built and exploded, and then the public was totally surprised and amazed. On the other hand, the public somehow anticipates the antimatter bomb, but we have known for a long time that it cannot be realized in practice.

  • by bluefoxlucid ( 723572 ) on Wednesday November 17, 2010 @05:22PM (#34260664) Homepage Journal

    I'm just saying that anti-matter is charge-reversed matter; but charge is really an irrelevant topic for the most part. Electrons (negative charge) are attracted to protons (positive charge). Electrons also move freely, since protons inhabit the nucleus of the matter and electrons orbit. All properties of matter are based on the interaction of electrons with the nucleus-- the orbital levels, valence shells, etc. Swap the charges and, reasonably, you have the same thing.

    If you swap the charges and find out that anti-SiO2 (glass, insulator) is a massive conductor of positrons and anti-copper is a massive positron insulator, something very strange has happened. Moreover, although this is "just conjecture," our existing laws of physics pertaining to chemistry would suddenly fall flat-- suddenly we'd find out that not only relative charge matters, but the DIRECTION of charge is immensely significant. That, to our current knowledge, wouldn't seem like an "interesting result of experimentation" -- it'd seem like completely implausible black magic.

  • by Anonymous Coward on Wednesday November 17, 2010 @05:37PM (#34260938)

    ATRAP has not demonstrated trapped hbar. Production, sure... but the Speck thesis was written long before the magnetic traps for trapping hbar even existed, let alone worked.

  • by Anonymous Coward on Wednesday November 17, 2010 @05:40PM (#34260994)

    interestingly enough, this happens one year in the future according to that article... Geneva, 17 November 2011

  • Don't we already have materials that care very much about the direction of charge? I suspect you'd have a hard time posting on Slashdot if the silicon in your computer stopped being a semiconductor.

    That's not to say that your claim of "it's just reversed charges; everything else is the same" is wrong, but there's certainly interesting science to be done. If nothing else, there's value in validating our assumptions. Our current models don't really account for antimatter, much like Newton's laws don't account for relativity. That doesn't mean they aren't useful, but it also doesn't mean we should simply accept them as a given instead of testing them in new environments.

  • Re:2012 (Score:3, Interesting)

    by mcgrew ( 92797 ) * on Wednesday November 17, 2010 @05:52PM (#34261246) Homepage Journal

    Don't worry, Gummal [slashdot.org] will take care of it. Or did will take care of it. Or will did take care of it.

    Or something. Damn, the mechanics of time travel give me a headache.

  • Re:antihydrogen (Score:4, Interesting)

    by John Hasler ( 414242 ) on Wednesday November 17, 2010 @05:59PM (#34261332) Homepage

    Getting the anti-protons and anti-electrons to combine into a single atom that stays at a low enough energy level that it can be contained for a significant amount of time is hard, especially since it is neutral and can't be contained with magnetic fields.

    I believe you can, by manipulating the dipole moment. Not easy.

  • by t2t10 ( 1909766 ) on Wednesday November 17, 2010 @06:05PM (#34261428)

    The gravitational properties of anti-matter are unknown. People assume that antimatter and matter all attract. However, it is possible that antimatter and matter repulse each other, or even that antimatter repulses antimatter gravitationally. Until it's measured, we won't know.

  • by painandgreed ( 692585 ) on Wednesday November 17, 2010 @06:07PM (#34261452)

    However, a particle and antiparticle won't annihilate if they do not come in contact with each other. If one half of the big bang were matter rich and the other half was antimatter rich, and were kept apart, then half the universe could be antimatter and half matter. Is there a way of detecting this?

    I believe the easiest answer to this is that in the very early universe, things were hot enough that everything was an ion (the first 300,000 years). Oppositely charged particles would have collided and where particles of like types of matter would not annialate, different types of matter would. Given the conditions of the early universe being so compact, one can consider it mixed and uniform. Thus, when the universe cooled to the point that normal matter could exist and not be instantly broken back into ions, all the anti-matter was long gone.

  • by Jellodyne ( 1876378 ) on Wednesday November 17, 2010 @06:17PM (#34261670)
    That's a bad analogy -- we believe our existing laws of physics (including relativity) DO account for antimatter. It should behave exactly like regular matter apart apart from the whole charge reversal deal, but we've never had enough to play with to find out. The reason we are asking the question of whether there is a disparity between regular matter and antimatter isn't because of anything we've observed, but because we live in a universe which appears to consist of almost entirely regular matter. The models we have of the early universe should lead to a universe in which neither type of matter is more prevalent. So the question is: are our models wrong or is there something different about antimatter which lead to regular matter dominating the universe?
  • by interval1066 ( 668936 ) on Wednesday November 17, 2010 @06:24PM (#34261754) Homepage Journal

    "Then again, I always keep my distance from the Vatican."

    Too bad, the Vatican is a warehouse of historical art and documents that span almost 20 centuries, from ancient Celtic gold captured by Roman Emperors to some of the most exquisite illuminated French manuscripts ever known. Sculpture by Michelangelo, paintings by Titian, medieval tryptics chased with gold filigree, original manuscripts by pagan authors such as Plato, Cato, and Virgil... really amazing stuff. But you'll never see it as you have obviously made the wise choice of avoiding Christian Ground Zero. They might zap you with their evil baptism rays. Good for you.

  • How do we know? (Score:2, Interesting)

    by Pro923 ( 1447307 ) on Wednesday November 17, 2010 @06:42PM (#34261984)
    How do we know that the universe is dominated by matter versus anti-matter? What is the scientific reason that we know that the next galaxy over isn't made completely of anti-matter versus matter?
  • by RobNich ( 85522 ) on Wednesday November 17, 2010 @07:14PM (#34262450) Homepage

    On the anti-matter side of the universe, they just call it "matter".

  • by Roger W Moore ( 538166 ) on Wednesday November 17, 2010 @08:38PM (#34263236) Journal

    Could it at all be possible that during the big bang, equal amounts of matter and anti-matter were created.

    No. It is one of the Sakharov conditions on the Big Bang. While your suggestion of "random" separation is technically possible the odds against it happening are so vanishingly small that it would be more reasonable to explain the extinction of the dinosaurs by spontaneous suffocation caused by no oxygen molecules entering any dinosaur's lungs just by "random chance".

    Even if you ignore the odds of it happening then there would still have to be a border between the matter and anti-matter that would be devoid of mass and we don't see a band stretching throughout the universe like this nor do we see it in the cosmic microwave background. So not only is your theory overwhelmingly improbable it is inconsistent with data.

  • by Anonymous Coward on Wednesday November 17, 2010 @09:02PM (#34263454)

    Sociological note: scientists realized that the atom bomb was a real possibility many years before one was actually built and exploded, and then the public was totally surprised and amazed. On the other hand, the public somehow anticipates the antimatter bomb, but we have known for a long time that it cannot be realized in practice.

    That does make perfect sense when you think about it -- the public are basically your anti-science.

  • by Kjella ( 173770 ) on Wednesday November 17, 2010 @09:56PM (#34263824) Homepage

    maybe you'd only need a few grams of antimatter to push a craft to/past the speed of light(?)

    We can't get to or past the speed of light, the power requirements increase asymptotically (that is, they grow towards infinity) as we approach light speed. And even at E=mc^2 its power is limited, it's estimated that 10 grams can make us reach Mars in one month. To get to a reasonable fraction of lightspeed we'll probably need tons, it also depends on how good we can make the engines use it.

    What you must understand is that we're extremely far from interstellar travel today. In practice we just get them a little past Earth's escape velocity of 11km/s or 0.004% of lightspeed, and the fuel required to push the other fuel makes increasing that hopeless. At that rate it would take ~100,000 years, by slingshotting around Jupiter we can get it down to 70,000 years but that's a one trick pony. Anti-matter is theoretically thousands of times stronger, meaning at least in theory we could have ships making the trip in 100 years or less.

    There are other theoretical designs which are - in the world of the already extremely theoretical - much more realistic than anti-matter though, but most of them are in the "many hundred or even thousands of years" range. Like for example designs based on a fusion reactor, that we still don't have a working version of. Anti-matter is just waaaaaaay out there as the ultimate theoretcial drive.

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