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When matter and antimatter collide?

  1. Jul 14, 2006 #1
    Would I be right in saying that the two are transfered to pure energy?
     
  2. jcsd
  3. Jul 14, 2006 #2

    EL

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    What is the definition of "pure energy"?
     
  4. Jul 14, 2006 #3

    ZapperZ

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    The question is also ambiguous in the sense that one also needs to know HOW they collide. If they come at each other at very high energies, then other particles can also be created. See what is going on at the Tevatron, and at LEP/CERN. All those exotic particles were created out of particle-antiparticle collisions.

    Zz.
     
    Last edited: Jul 14, 2006
  5. Jul 14, 2006 #4

    DaveC426913

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    In the "ideal" situation though, is it not true that the product of a matter-antimatter collision is simply gamma radiation?

    Thus, the short answer to his question is "Yes, under the right circumstances"?
     
  6. Jul 14, 2006 #5
    To be honest, not really sure about the phrase 'pure energy'
    Studying A Level Physics at the moment and I stumbled upon this article.

    From http://science.nasa.gov/headlines/y2000/ast29may_1m.htm

    May 29, 2000 -- What do you think of when you hear the word "antimatter?" Something exotic, something unreal? Something about your Chief Engineer not being able to keep the containment fields up during battle?

    Well, to a few NASA and university researchers, antimatter may just be the future of human space travel. When it comes to packing a punch, antimatter/matter reactions can't be beat. When a particle and its antiparticle meet, they annihilate each other and their entire mass is converted into pure energy.



    Which made me wonder if matter can be turned into pure energy could pure energy be turned into matter. Just curious more than anything.
    Please excuse my ignorance.
     
  7. Jul 14, 2006 #6

    ZapperZ

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    This is why, in many cases, when one asks a question such as this, it is always better to cite where one read about such a thing. Often, the question came out of a misinterpretation of what is being conveyed. So we always prefer that there is a citation of the source.

    Zz.
     
  8. Jul 18, 2006 #7
    I don't think I could understand how energy would not always be "pure". Probably just the wording they use to make the article sound cooler. And since they see the need to make their article sound cool they obviously aren't going to use complex examples and say stuff like "well, not really, but in the specific complicated circumstances we use them in they will". I would take the article as saying that it is possible.

    As for your question It would seem logical that if antimatter/matter collisions can convert whole masses into energy then energy could possibly be converted back into mass. Actually i wouldn't be supprised if it does happen, but I can't think of any examples right now (damn brain).

    ~Gelsamel
     
  9. Jul 19, 2006 #8

    ZapperZ

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    It depends on what you define by your usage of the word "pure". Is the energy in a moving object "pure"?

    Furthermore, the energy is converted into mass all the time. See chemical reactions and all those particle collisions at the Tevatron, JLab, and RHIC. That is why they need to collide those particles/atoms at such high energies. Those energies are converted into all the exotic matter. One can also create matter out of pair production - this is the most common way to create positrons.

    Zz.
     
  10. Jul 19, 2006 #9
    El/fatoomch: Energy is a property. Something has energy. You can't have energy on its own. So "pure energy" is the wrong concept. You can think of this by thinking about a colour. Something can be red. But red can't exist without the something that is red.
     
  11. Jul 28, 2006 #10
    I was wondering, since everything has an antimatter, do we have an anti? If we do, what would happen when we would meet? Would we destroy ourselfves?(Sort of how devil and angels do)
     
  12. Jul 28, 2006 #11

    jtbell

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    If you consider photons to be "pure energy", that is. :uhh:
     
  13. Jul 28, 2006 #12
    Indeed! Every morning I put on a layer of perspirant, and then a layer of anti-perspirant. It's a refreshing burst of energy.
     
  14. Jul 28, 2006 #13

    selfAdjoint

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    Famous comic poem:

     
  15. Jul 30, 2006 #14
    Consider this case, collide a matter deuteron [NP] with an antimatter triton [[itex]\overline{N}\overline{P}\overline{N}[/itex]], pure energy should not be the outcome of the interaction since the matter and antimatter have asymmetric mass units.
     
  16. Jul 31, 2006 #15
    So you are saying that when human and antihuman would shakehand, we would just turn into energy?
     
  17. Jul 31, 2006 #16

    selfAdjoint

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    What the poem said, pretty correctly, was gamma rays, that is to say highly energetic photons. There would probably be a lot of other particles too, as when in Fermilab a proton and an antiparticle collide and annihilate, conservation of energies allow a lot of massive particles like the top quark and its antitop to come into observability.

    Added: As others have pointed out, energy is a property, just as the color red is. "Pure red" is never found by itself, but only as the color of some red thing. And energy is only found as the energy of some energetic thing. In quantum mechanics that means a field or a particle. So if a thing and its antithing anihilate - disappear - their energy can't just exist by itself, and Nature has to produce something to have the energy so the conservation books can be balanced. That's very unscientific talk, but maybe it gets the point across?
     
    Last edited: Jul 31, 2006
  18. Jul 31, 2006 #17

    DaveC426913

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    Each type of fundamental particle has an antimatter counterpart. That has nothing whatever to do with macro structures in the universe having counterparts.
     
  19. Aug 6, 2006 #18
    Im a newb and know virtually nothing about physics but is all the matter turned into energy and is any matter produced in annihilation?
     
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