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Matter/Anti matter

  1. Feb 10, 2010 #1
    Please explain the process of matter anti matter and how it could be used in space travel
  2. jcsd
  3. Feb 10, 2010 #2
    When matter and antimatter annihilate all the mass is converted to energy. This makes antimatter the most efficient fuel possible. Mass of the fuel is critical for space travel, so it also makes antimatter ideal fuel for space travel.

    Just to give you some idea of numbers: you can match entire output of three space shuttle main engines during entire liftoff sequence with just 0.134 grams of antimatter - matter combination. Scary, isn't it?
  4. Feb 11, 2010 #3
    Well It's the kind of stuff That makes us a phase 2 society.
    Are there current work in progress to make this happen?
  5. Feb 11, 2010 #4


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    They are creating anti-matter in labs, but the costs are prohibitive at this point. (~Several tens of trillions of dollars per gram)

    Here's a paper on it:
    http://www.engr.psu.edu/antimatter/Papers/NASA_anti.pdf [Broken]
    Last edited by a moderator: May 4, 2017
  6. Feb 12, 2010 #5
    Thanks for filling me in on this matter heh Pun completely intended
  7. Feb 12, 2010 #6
    As someone studying physics, it is very easy to get bogged down in the difficulties and mathematics and lose sight of the grand ideas which fascinated me as a child. Thanks for that link, I found it to be a very interesting examination of something at the intersection of physics and science fiction.
  8. Feb 12, 2010 #7
    Of course, storage of >~1g of antimatter in one place would present, I would have to assume, essentially insurmountable risks.
  9. Feb 12, 2010 #8


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    Puh-leeze. It can be stored in a cannister the size of a tennis ball can and contained with some dry cell batteries. I saw it in Angels & Demons.

  10. Feb 12, 2010 #9
    But I am assuming that :biggrin: But any failure would be so spectacular the entire device would have to be legally regulated :biggrin:
  11. Feb 12, 2010 #10
    I have questions about this too. Has anyone ever seen what antimatter looks like and what triggers antimatter to travel back in time? If antimatter does travel back in time then, where is the proof? Are there equations that explain how it goes back in time or has someone actually seen antimatter disappear in front of them to say that the antimatter opened a new dimension?
  12. Feb 12, 2010 #11


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    It looks the same as matter. Photons are their own antiparticle, so when an antimatter atom emits a photon it gives no indication that it came from antimatter.
    It doesn't. where did you read this?
  13. Feb 12, 2010 #12
    Firstly anti-matter does not exist in nature. Secondly when created, in lab, it takes more energy to create it than what can be yielded from it (thermodynamics). SO it is not viable means of powering anything.
  14. Feb 12, 2010 #13
    You are completely missing the point. It is useful as a storage mechanism.
  15. Feb 12, 2010 #14
    We need an anti-matter container to store this anti-matter. The container would explode if we touched it, so we need some anti-matter gloves. The gloves would explode if they touched our hands so we need anti-matter skin. We would then explode because we touched the earth, therefor we need an anti-matter earth.

    Now how are we going to use anti-matter when anti-matter has become matter?
  16. Feb 12, 2010 #15
    The answer is no because of the very fact that currently only a few atoms of anti-matter can be produced and that transporting such anti-matter is mind boggling. Any contact with normal baryonic matter and it will simply annihilate itself.
  17. Feb 12, 2010 #16


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    What is going on here??? :grumpy:

    Of course it does. :grumpy:

    Neither do Ni-CAD cells or Liquid Hydrogen, but they are an excellent way to power something.

    As Phyisab**** points out, most of our propulsion systems are really storage devices. Producing the potential energy that is stored in this those batteries is always energy-intensive.

    All we need is a magnetic bottle.:grumpy:
  18. Feb 12, 2010 #17
    Thanks for ruining my whole theory Dave.:frown:
  19. Feb 12, 2010 #18
    Provide your evidence that anti-matter DOES exist in nature.
  20. Feb 13, 2010 #19


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    Feel free to start http://en.wikipedia.org/wiki/Antimatter#Origin_and_asymmetry".

    Last edited by a moderator: Apr 24, 2017
  21. Feb 13, 2010 #20
    For Dave, may I point out this article produced by CERN - http://public.web.cern.ch/Public/en/Spotlight/SpotlightAandD-en.html [Broken]

    Admittedly, it is primarily focused on angels and demons but you will understand why anti-matter does not exist , exist being the key word, in nature.

    EDIT: Dave, you are a PF contributor and supposed science advisor. I thought PF was a serious site promoting education. If you believe this you should stop referencing unregulated WIKIPEDIA and start referencing papers from scientific authority.
    Last edited by a moderator: May 4, 2017
  22. Feb 13, 2010 #21


    I followed the wikipedia citatation. The statement that antimatter does not exist is an enormous generalization. Of course it exists.
    Last edited: Feb 13, 2010
  23. Feb 13, 2010 #22


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    I referenced Wiki for your benefit. It is a good place for you to start reading up on the subject if you're going to discuss it.

    If someone comes on the board and says "F=ma is wrong", I'd do the same thing: "start here with your learning".

    Your unilateral statement that it does not occur in nature is wrong. You can certainly modify it to say that it doesn't exist in great enough quantities and doesn't exist for long enough to be useful, but that would be a different claim.

    Yes, an FAQ aimed at the uneducated who want simple answers about a film. Here at PF, it is not good enough to be so general.
    Last edited by a moderator: May 4, 2017
  24. Feb 13, 2010 #23

    Interesting, however, if you read the article it is not definitive if anti-matter exists in nature or not. There is some debate as to whether the detected 511 keV transmission spectra is caused by a positron-electron collision. Though thank-you for providing something not from wikipedia.

  25. Feb 13, 2010 #24
    Please read that paragraph again. 511keV is the rest mass of an electron or positron. There is very little doubt the line is caused by electron positron annihilation.
  26. Feb 13, 2010 #25
    Elaborate if you wish to win me over.
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