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Antimatter proven by CERN

  1. Feb 23, 2005 #1
    Humble apologies if a thread regarding this has already been started.

    I was just browsing through the net and got to read about antimatter.It is already proven by CERN that it is not a rumour but truth that it does exist and CERN is producing it in minimal amounts.It is something which I believe would change the whole phase of the world as we finally have a 100% efficient energy source.But with it being so very volatile that when it comes in contact in with any sbstance in the air, it would lead to an annhilation.Hence, all those antimater specimens are kept under vacuum.

    But the big debate is weather it would fall in the hands of the evil, i.e used to make the most dangeround wepon known to man.Loads to think about and look forward to I believe.
  2. jcsd
  3. Feb 23, 2005 #2


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    One may wish to refer to http://hussle.harvard.edu/~atrap/News/2002/PressRelease.pdf


    Anti-matter/matter annhiliation is effectively 100% efficient, The main reactions of proton-antiproton (and neutron-antineutron) annihilations to several pions and photons, ie. [itex]p + \bar{p}[/itex] and [itex]n + \bar{n}[/itex] to multiple [itex]\pi^+, \pi^-, \pi^o, \gamma[/itex], and then the charged pions decay into appropriate muons and muon-associated anti-neutrinos and the muons then decay into electrons and neutrinos. The neutral pions decay into gammas or gammas/electrons.

    See - http://hyperphysics.phy-astr.gsu.edu/hbase/particles/hadron.html#c2

    Overall, anti-matter is not a practical energy source on earth since it takes way more energy to make that one would recover. It does conceivably make a very nasty weapon, assuming one can confine a substantial quantity. (Personally, I think mankind has better things to do than devise ways of annihilating itself).

    IIRC, maximum production rates of anti-matter are on the order of pico-grams per year, although I have seen one site that claims up to one gram/year, but that seems to high, and anyway it is certainly not confined, but rather in beam form.

    For more practical applications of anti-matter see - http://www.engr.psu.edu/antimatter/documents.html [Broken]
    Last edited by a moderator: May 1, 2017
  4. Feb 23, 2005 #3
    Nope, sorry but I (entropy) won't allow you to have 100% efficiency. :devil: Bwhahaha!

    Although anti-matter is best fuel in terms of energy per unit mass. It probably won't have any use in producing power other than for spacecrafts. You see when anti-matter is created you need energy to create it. Energy that comes from solar, nuclear, coal, or what have you.
  5. Feb 23, 2005 #4


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    Entropy is a statistical mechanical phenomenon; it does not exist in the microscopic domain. The conversion of matter and antimatter into radiation is 100% efficient.

    - Warren
  6. Feb 23, 2005 #5

    But in the macroscopic domain, would you agree that a proporton of photons would be lost as heat in the process? Hence the efficiency of the system would be determined by this factor, and the entropy increase.
    This would be unavoidable on the large scale reactions that may be required to produce energy in the future. Ultimately 100% efficiency is pretty much unattainable in practicality.
  7. Feb 23, 2005 #6


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    The manufacturing problem is indeed formidable, here on Earth. However, it may be possible (in the distant future) to harvest antimatter from a nearby, solar-powered antimatter generator: the sun. Solar astronomers have observed phenomena which indicate that some solar eruptions can produce more than a pound of antimatter.
    Last edited by a moderator: May 1, 2017
  8. Mar 2, 2010 #7
    Re: Antimatter.

    I was thinking, wouldn't it be theoretically possible to set up a large array, made up of the same material used to produce antimatter on earth, and harness the huge amount of protons in the solar wind to create antimatter. The high volume of protons should produce at least grams of antimatter over the course of a year, depending on how close the array is to the Sun.
  9. Mar 7, 2010 #8
    Re: Antimatter.

    It takes at least a 6 GeV proton hitting a stationary target to produce an antiproton. This is equivalent to about 2 GeV in the center of mass. This is what Segre and Chamberlain did about 1956 to discover antiprotons. The solar protons are very low energy.

    Bob S
  10. Mar 14, 2011 #9
    Re: Antimatter.

    this is like the film angels and demons, but you would need a heck of a lot of time and energy t make nearly enough, cern has only made a tiny amount :D
  11. Mar 14, 2011 #10

    Meir Achuz

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    Re: Antimatter.

    Antimatter is nothing new. The first experimental observation was by Carl Anderson in 1932 for which he receive the 1936 Nobel prize.
    Copius beams of antimatter have been used at Stanford and elsewhere for many years, and for medical purposes as well.
    The CERN LHC is just the newest of many antimatter factories.
  12. Mar 15, 2011 #11
    Re: Antimatter.

    Certain radioisotopes provide a good source for anti-matter .
    You're not evil are you? :))
    OK; Sodium 22 is a positron emitter, and you get gammas and neutrinos to boot.
    http://discover.positron.edu.au/making-our-own-antimatter/radioactive-decay/ [Broken]

    Fluorine-18 is another ....positrons....had it put in my blood one time...not fun.
    Be careful...

    Last edited by a moderator: May 5, 2017
  13. Mar 16, 2011 #12


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    Re: Antimatter.

    Dare I ask why?
  14. Mar 16, 2011 #13
    Re: Antimatter.

    Positron Emission Tomography.
    They tell me I will die if I don't let them do it. They call themselves radiation oncologists ... I call them terrorists.
    They inject me with radionuclides, tell me not to move for 1 hour, positrons get into all my organs, the resultant gamma rays shoot out from everywhere inside my body....I pray... they take pictures.
    $6500 per pop.
    If you are wondering why your Mediacal insurance premiums are going up, you can blame me....and Obama of course. :))

  15. Mar 21, 2011 #14


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    Re: Antimatter.

    If they inject positrons into your body, shouldn't you be anihlated in a matter of minute seconds?!
  16. Mar 22, 2011 #15
    Re: Antimatter.

    Er...no; they may have tried to annihilate me, but I'm still here.
    Positrons only annihilate with electrons...so they didn't get my neutrons and protons, he, he. :)) I may have become a little more electropositive than before, but not annihilated.

    I was far more concerned with the coincident gammas that blasted through my organs... hopefully my DNA survived, and I won't grow an extra ear or something.
    The F(18) half-life is just under 2 hours, so I wasn't emitting gammas for more than a day or so.

    However, I did think about walking through the (heavily populated) airport security system to see if I could produce enough panic to "clear out" the airport. :smile:

    Last edited: Mar 22, 2011
  17. Mar 22, 2011 #16


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    Re: Antimatter.

    It's been addressed already but making 1 gram of antimatter would cost you more than the energy released from that 1 gram of antimatter being annihilated. However whilst it doesn't represent the perfect energy source antimatter would be a great battery, a few grams of antimatter properly contained and able to be released in minute (pico/nanogram) quantities could keep things like deep space probes and the like operational for hundreds of years.

    You've potentially stumbled on an answer to the Fermi paradox there (if space is so big and old and life is possible it should have happened many times, that being the case where the hell is everybody?). The energies needed to run an interstellar civilisation complete with relativistic transport implies antimatter production on the order of megatonnes per year. It would be like if every plane on Earth was fitted with a nuclear bomb that went off when the plane crashed. To easy for nutters to destroy worlds and wars to progress from opening-fire to genocide
  18. Mar 27, 2011 #17
    Re: Antimatter.

    Is this reaction equation perfectly matched experimental results?
    high energy ------->N proton + N anti-proton
    high energy ------->N quark + N anti-quark
    i.e., Has the same moles of proton(or quark) and anti-proton(or anti-quark) production been already proved experimentally?
    Last edited: Mar 27, 2011
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