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Mesons Flip Between Matter and Antimatter 150

Posted by kdawson
from the make-up-your-mind dept.
steve writes "A team of over 700 physicists at Fermilab's Tevatron accelerator have observed the B-sub-s meson oscillating between matter and antimatter states at 3 trillion times a second. From the Fermilab press release: 'Immediately after the Big Bang some 13 billion years ago, equal amounts of matter and antimatter formed. Much of it quickly acted to annihilate the other, but for little-understood reasons, a bit more matter than antimatter survived, providing the universe with the planets, stars and galaxies visible today.' The Standard Model predicted the oscillation, and Fermilab has been working for 19 years to confirm it. The announcement is good press for Fermilab, which is pushing Congress to build a new 18-mile-long International Linear Collider."
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Mesons Flip Between Matter and Antimatter

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  • by Anonymous Coward on Thursday September 28, 2006 @04:18PM (#16236007)
    or Republicans would have resorted to calling these "Kerry particles"....
    • by creimer (824291)
      Yeah, now they can call them "Bush-whacked particles". Although what got whacked depends on where you stand politically on the Big Bang.
    • The scientists could be locked up for using this to prove the Earth is greater than 6000 years old.

      Non Creationist speak = disagreeing with Bush = enemy combatant
    • A little off-topic, but fun story. It was 2004. I was in a computer science class - I forget the official name, but we were doing circuit-level stuff with transistors and NAND-gates and multiplexers and what-have-you. Those of you who have taken a class may be familiar with a particular configuration of NAND gates which, for example, stores one input when the other is strobed. These are known as bistable multivibrators [wikipedia.org] or, more commonly, "flip-flops". This simplest one is the SR flip-flop (set/reset) but on
    • by evilviper (135110)
      or Republicans would have resorted to calling these "Kerry particles"....

      More likely they'd have burned the scientist at the state for heresy.
  • Only a bit (Score:5, Funny)

    by 0racle (667029) on Thursday September 28, 2006 @04:20PM (#16236041)
    a bit more matter than antimatter survived, providing the universe with the planets, stars and galaxies visible today
    Did they just call the visible universe only a bit?
  • The Big Bang was the Big Mistake because more matter survived than anti-matter to form the universe instead of returning to the void. Philosophers are going to have a field day with this one.
    • by Potor (658520)
      unsound conclusion: mistake implies intentionality.
    • by aiken_d (127097)
      Look on the bright side: if more antimatter had survived, we would all be made out of antimatter and living on antimatter planets. Scary!
      • Scary? I don't think it would really matter....
      • Except that we would call this substance matter, and, what we now call matter would be deemed antimatter. AFAIK, a system made totally out of antimatter will behave exactly the same as a system made out of matter in an identical configuration...

        Any real physicists care to confirm/deny?
        • by XenoRyet (824514)
          IANAP, but I have read up on the subject, and that was my understanding as well.
        • by quadong (52475)
          Very nearly true. There's a small catch, and that's CP violation, which does allow matter and anti-matter to be distinguished by an experiment, even if the experimental apparatus is also of unknown (anti-)matter composition. (In other words, to use an oft-quoted example, if aliens are approaching the earth and we want to know whether we are made of matter or anti-matter, there are tests we can ask them to run inside their ship that will answer the question. It is not necessary to send any matter down fro
          • if aliens are approaching the earth and we want to know whether we are made of matter or anti-matter, there are tests we can ask them to run inside their ship that will answer the question. It is not necessary to send any matter down from the ship to see if it explodes

            Unless the aliens are also traveling backwards in time and made of antimatter. Then we're screwed.

            (actually there IS another part of CP called T which is time reversal, and is theorized to always cancle out the CP violation in the math)

        • I am not a Real Physicist (TM), but I've got a degree in Mechanical Engineering; let's see if I can take a stab at it.

          The short answer is that, yes, a sufficiently motivated particle physicist could tell the difference between living in a universe made entirely of matter and one entirely made of antimatter.

          Here's a (partial) long answer: I read an article in Scientific American in about 1991 that explored how Alice (of Wonderland and Through the Looking Glass fame) could tell which universe she was in by u
          • by bar-agent (698856)

            Alice would observe how certain sub-atomic particles decay under rare conditions, and the observed behavior would indicate a right-handed matter universe or a left-handed antimatter universe.

            I knew she was an intelligent and imaginitive girl, but I didn't know she was smart enough for that!

            Although, I guess hanging with the Cheshire Cat and shrinking to the size of a mouse would tend to direct one's interests towards subatomic quantum physics. :)

      • Look on the bright side: if more antimatter had survived, we would all be made out of antimatter and living on antimatter planets. Scary!

        But wait! What... What if we ARE all made out of antimatter and living on antimatter planets?!

        /me runs off to write a really, really bad movie script

    • Isn't matter and energy the same thing? E=m*c^2? So shouldn't energy have turned back into matter at some point? Or is this a discussion similar to why life on earth has the chemistry it does when the "lightning in a bottle experiment" develops equal amounts of "left" and "right" handed molecules? Or could the universe have a preference, and condense out matter instead of anti-matter?

      BTW, I AM NOT A PHYSICIST. (If it isn't aparent already.)

      Phil
      • by creimer (824291)
        I have no idea. Haven't read enough science fiction to determine if molecules are left- or right-handed. It's all greek to me! :P
      • The Dirac equation which is the governing equation for matter that takes into account relativity (as opposed to the Schrodinger's equation which doesn't) predicts the existence of antimatter. And the Dirac equation specifically takes into account the equivalence of matter and energy.
      • by trip11 (160832) *
        If I recall back from my classes, at the start of the universe matter and energy flipped back and forth all of the time. However the universe was expanding, some of the energy went to inflating the universe. Sort of how when you lower the pressure in a volume, you lower the temp as well. So the energy (photons) couldn't switch back to matter. Going one step more, matter can only convert back to energy when it hits antimatter (more or less). This is where the article comes in. If you can flip between m
      • Actually it should be E^2=M^4*c^4*p^2*q^2, but using the actual formula makes the solutions strange, of course oscillating between matter and antimatter 3 trillion times a second is pretty strange too. The other thing this emphysises is how little we really understand about really basics of physics, I bet even to the experts it's jabberwocky most of the time.
      • Re: (Score:3, Informative)

        by maxwell demon (590494)

        Isn't matter and energy the same thing?

        No. Matter is, well, matter (i.e. electrons, protons, etc.). Energy is a property of matter/fields.

        E=m*c^2?

        The m here is "mass", not "matter". Again, mass is a property of matter.
        BTW, this equation holds only for matter at rest; generally it's E^2 = (mc^2)^2 + (pc)^2.

        So shouldn't energy have turned back into matter at some point?

        Normally matter and antimatter are produced in equal amounts. Note that antimatter has positive energy (and positive mass) as well.

      • Energy did (and does) turn into matter and anti-matter, and vice versa (matter+anti-matter->energy). In the beginning, if energy had done both matter and anti-matter in exactly equal parts there would have been a continuing creation and annihilation of matter and no large scale structure would exist in the universe. It would be mostly energy in the form of light.
    • "In the beginning the Universe was created. This has made a lot of people very angry and has been widely regarded as a bad move."

      -- Douglas Adams, another man who thought that the universe could be a mistake.

    • by Y2 (733949)
      The Big Bang was the Big Mistake because more matter survived than anti-matter to form the universe instead of returning to the void.

      The "initial" (whatever that turns out to mean) mixture mat have been perfectly equal. But departure from thermal equilibrium due to the expansion, combined with asymmetric rates for reactions involving matter vs. antimatter, lead to a small imbalance.

  • by Stanistani (808333) on Thursday September 28, 2006 @04:21PM (#16236081) Homepage Journal
    I say this oscillation should be called the "Quagmire Effect."
    • by richdun (672214)
      As much as I love Family Guy, I think the Bush Administration has that term trademarked.
  • I oscillate (Score:2, Funny)

    by Anonymous Coward
    between (-1, Troll) and (5, Funny)
  • by Chagatai (524580) on Thursday September 28, 2006 @04:40PM (#16236469) Homepage
    I think these mesons have caused some problems on the Slashdot main page. When looking at the article, I saw this:

    Science: Mesons Flip Between Matter and Antimatter 7 of 6 comments

    Someone must have snuck in an antimatter posting or something.

    • And it quickly annihilated one of my own normal matter posts.

      It was +5 Insightful, Interesting AND Funny as well, I'm telling you!
    • by Daemonstar (84116)
      Science: Mesons Flip Between Matter and Antimatter 7 of 6 comments

      Eek, I think it's spreading to other stories!

      Games: Peter Jackson on the Future of Storytelling 6 of 4 comments
  • by Anonymous Coward on Thursday September 28, 2006 @04:59PM (#16236825)
    B-sub-s Meson doesn't quite roll off the tongue in the press release.

    Since these Mesons flip between matter and anti-matter regularly, I propose calling them...

    Freemesons.
    • Actually, normally it is just called the "Bs". Yes that is true. I work at CDF (the collaboration that produced this result) during the summers, and for CDF during the school year.
  • 'Immediately after the Big Bang some 13 billion years ago, equal amounts of matter and antimatter formed. Much of it quickly acted to annihilate the other, but for little-understood reasons, a bit more matter than antimatter survived, providing the universe with the planets, stars and galaxies visible today.'

    Actually, that quote is not from the Fermilab press release. It's from this Chicago Tribune article [chicagotribune.com] which is a little more down-to-earth for us non-physicists.

  • Oh! Shiny! (Score:5, Interesting)

    by Dr. Eggman (932300) on Thursday September 28, 2006 @05:28PM (#16237277)
    Say what you will about the 18-mile-long International Linear Collider, but it is shiny; and I like shiny!



    I certainly expect many /.ers here to grumble and groan about the ILC idea, but I like it. Even if it is a colossal expensive project in a time of world-striding debt, I think it is ultimatly in the nations best interest to build the ILC. First, it'll go a ways towards convincing the rest of the international that it need to be built here in the United States.

    The US is the world leader in physics research, one of the few fields we still can claim that in. We have 8 of the world's Fusion power research facilities (and 4 more have been decomissioned for a total over time of 12,) more than the other nation in the world combined (if you exclude the ITER which we have rejoined.) But by letting the ILC go to Europe or Japan, we'd be deflating our physics potential. The ILC will be unparralleled in its power; attracting the brightest minds in physics today with real opportunity. If the ILC is in America, we'd be very attractive to those bright minds and with them opportunities to put their minds to work for our country. The LHC (slated to be the largest particle accelerator completed in 2007) would be the only comparable facility.

    I think we lost out on a real opportunity by not building the superconducting supercollider. Whether or not you believe it was just being funded to show up the Soviets or not, I can't help but place it's closing as the begining of a distinct lack of focus on science in the US that is only getting worse today. Funding the ILC would at least be a demonstration that America still has interest in its scientific future, and at best would help us get the facility here and mark a hopeful turn in trends.

    But showboating our physics prowess and bringing in a few eggheads isn't the only real benefit. The projects like the ILC and other big time projects like the ISS can invigorate the mind of our young children, prompting them to take an early interest in science and physics; the key factor in our nation's future. How many children do you know who want to be an astronaught because they hear about NASA and it's contributions to the ISS? It doesn't matter if it's international, as long as we participate in a meaningful way it gets talked about and can influence our kids.

    So I think we should fund the ILC. Lets do it for the children.
    • Re:Oh! Shiny! (Score:5, Insightful)

      by kaffiene (38781) on Thursday September 28, 2006 @05:37PM (#16237441)
      Science shouldn't be an intra-nation dick measuring competition, it should be about advancing knowledge. I personally don't care where these things get built so long as they get built.
      • Re: (Score:3, Interesting)

        by evilviper (135110)
        I personally don't care where these things get built so long as they get built.

        It's not some trivial "bragging rights" move. Brain drain is REAL, and very important for the economies of nations.

        WWII pushing so many scientists to move out of Europe, is one of the main reasons the US became the top superpower in the world.
        • by kaffiene (38781)
          So? I don't care if the US remains a superpower. I'd argue that it would be good for the world if they became just an ordinary country rather than a wanna-be global cop.
          • by C_Kode (102755)
            WARNING: US HATE MONGERING!!!

            Don't worry, we still love you...
            • by kaffiene (38781)
              Warning! Knee-jerk reactionism!

              Not liking US foreign policy is not at all "US HATE MONGERING".

              Or are you another one of these morons who can't see a world were people aren't either entirely with you or entirely against you?
          • by evilviper (135110)
            I don't care if the US remains a superpower.

            The point remains. It's not a trivial issue, as you make it out to be.

            I'd argue that it would be good for the world if they became just an ordinary country rather than a wanna-be global cop.

            You could argue that... You'd be so wrong it's not funny and showing your complete ignorance of 20th century history... but you could argue that.
            • by kaffiene (38781)
              ...only if you can show that one can dislike US foriegn policy if and only if they're ignorant of 20th Century history, which you clearly cannot. It's an utterly ridiculous inference.
              • by evilviper (135110)

                ...only if you can show that one can dislike US foriegn policy if and only if they're ignorant of 20th Century history, which you clearly cannot.

                Quite easily... There is ample evidence that the US as a superpower has had a tremendous stablizing affect on the entire world. Though it has not ended war, it has dramatically decreased the number of people who die, yearly, in armed conflicts. Not to mention record economic prosperity around the globe.

                It's one thing to be critical of certain, specific policies.

                • by kaffiene (38781)
                  This is clearly difficult for you. I'll write it slowly:

                  You

                  Need

                  To

                  Show

                  that one can dislike US foriegn policy if and only if they're ignorant of 20th Century history...

                  which you clearly cannot.

                  Nice rant, but it didn't answer my point at all.

      • Re: (Score:3, Interesting)

        by Fastolfe (1470)
        Let's assume for a moment that you live in a country that doesn't "compete" in this respect. Some scientists have a new idea, and they propose their idea to your government. You decide that it isn't worth the money and pass on it. They go to another government, and propose it to them. They decide to do it. Your scientists move. Your country now has fewer smart people than it did before.

        Repeated enough times, this trickles down into education and your country's economy. You are now less capable than y
        • by kaffiene (38781)
          I understand why states sponser science, I don't understand why any individual geek should care whether science is done in the US, UK, USSR or any other place in the world. As long as we all stand on the shoulders of others, it's all the same to me.
          • by Fastolfe (1470)
            I'd prefer to be surrounded by smart people, and I'd prefer to see my country (thus me) benefit more than others.
    • Re:Oh! Shiny! (Score:5, Informative)

      by wass (72082) on Thursday September 28, 2006 @07:07PM (#16238669)
      I'm a doctoral student in physics (experimental condensed matter), and I can tell you that the US is already showing signs of declining in its lead in the sciences. While we are still very strong, many other regions (eg China and Europe) are also revealing trends of outpacing us.

      At the 2006 March Meeting [aps.org] of the American Physical Society, some of us physicists (students and professors) went to Washington DC to lobby our Congressmen (see Congressional Visits [aps.org]) about looming shortfalls of hard sciences in the USA and to encourage them to vote on upcoming bills to increase science funding.

      There is alot of eye-opening data showing how Europe and Asia are significantly outpacing the US in terms of funding basic science education, in terms of the number of undergraduate and graduate degrees in the basic sciences, etc. Graphs plotting hard sciences degrees offered per year show the US lagging quite significantly (where we used to be leading 5+ years ago). Such trends are fairly worrisome because the hard sciences are tightly coupled to engineering and industry. Industries tend to attract to places with higher concentrations of scientists, so the US losing scientists will manifest itself in loss of industries down the line.

      These are the kind of things that Senators and Representatives care about. To complicate matters there is a lag between industry and science, meaning that changes in science funding and numbers of scientists now won't be manifest significantly in industry until a decade or longer out. I met with two of my Congressmen and one of my Senators (really with their staffers), who luckily were familiar with this and assured us their bosses would be voting for the upcoming legislation to increase funding.

      I come from a blue state, where the Congressmen are usually liberal with such education and funding programs. The red stater politicans were more hostile to funding sciences without seeing immediate industrial rewards. Such short-term thinking in those cases is what is leading to the decline of US scientific leadership.

      On a different note, I've also seen major shifts in the attraction of foreign students to the US over the past few years. The Bush administration his been cracking down on student visas, which is also hurting our lead. In my department, within the past 3-4 years, each year a handful of good students accepted to the program are denied visas to enter the US (usually from China). Well, these guys aren't going to put their career on hold, and they'll go elsewhere. Many more foreign students are going to Canada and Europe, for instance, and the great brain drain that the US was known for the past few decades is beginning to show signs of reversing.

      Anyway, I just wanted to throw in my two cents becuase I specifically lobbied my Congressmen about this very issue only six months ago.

    • Well, realistically, anyone who complains about the cost of these things is a fool of the highest calibre. Science represents a tiny, tiny fraction of the any nation's budget. An absolutely, amazingly small amount. Most money gets spent on war and beauracrats. Things like the ILC, the space program, ITER, welfare programs, protecting the environment, not letting psychopaths out of jail just to make space, snipers that shoot lobbyists and non-nude PETA activists on sight, are so inexpensive by contrast t
  • by vondo (303621) * on Thursday September 28, 2006 @05:36PM (#16237421)
    Disclaimer: I am a particle physicist.

    This is a really cool measurement. But the summary is a little sensationalist. First, the B-sub-s is not the only particle that oscillates between matter and anti-matter. Kaons have been known to do this for decades and regular B mesons have been observed to do this for 20 years or so. In fact we've known for a long time that B-sub-s mesons oscillated. What we didn't know is how fast. We knew "really fast" but not a number.

    In fact, the cool thing is that a B-sub-s, statistically, will oscillate many times between particle and anti-particle before it ultimately decays. Nothing else in this class of particles will do that. For instance, most B mesons will not change flavor before decaying.

    But, this is a very interesting result.
  • by Mr Europe (657225) on Friday September 29, 2006 @07:29AM (#16243053)
    "antimatter states at 3 trillion times a second."
    But that's only American trillions (10EXP12) and not the real trillion (10EXP18)
    10EXP Am RestOfTheWolrd
        6 million million
        9 billion thousand million (or milliard)
      12 trillion billion
      15 quadrillion thousand billion (or billiard)
      18 quintillion trillion

    For really big numbers, see:
    http://www.uni-bonn.de/~manfear/numbers_names.php [uni-bonn.de]
    • by Cervantes (612861)
      I think it has to be measured in "Rest of the World" numbers, because they didn't express it in VW Bug Headlights per Library of Congress.

      (yeah, that's kinda lame, but I couldn't think of an Americanized measure of rapidity of movement, so I went with energy insted. Deal.)
  • Your brother is oscillating between matter and antimatter states at *3 TRILLION times a second*, and all you can do is sit around all day watching the Cartoon Network!!

    -Eric

"Pascal is Pascal is Pascal is dog meat." -- M. Devine and P. Larson, Computer Science 340

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