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Speed of light?

  1. Oct 23, 2005 #1
    Hey I dont know if this in the right catagory but i'll ask it anyway.
    I was watching TV when some documentary came on, it was on some particles called antimatter(refered as antiphotons,antineutrons,etc)and the person said if you bash a bunch of photons at the speed of light at some type of metal(I think Titanium or tugsten) it will seperate in to antimatter.

    He also said if you used it,it can propell something at the speed of light.

    Is this true if it is can you explain it?:confused:
  2. jcsd
  3. Oct 28, 2005 #2


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    This is not true.

  4. Oct 28, 2005 #3
    From what I understand is that in a particle accelerator you can create a small amount of anti-matter, but I don't know how it works but I am going to look into it.
  5. Oct 28, 2005 #4
    Here is a good website I found about a month ago and forgot all about it till now:

    http://livefromcern.web.cern.ch/livefromcern/antimatter/ [Broken]
    Last edited by a moderator: May 2, 2017
  6. Oct 28, 2005 #5


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    You must have mis-heard. Certainly it would make no sense to talk about having electrons, protons, etc. at the speed of light and then use the energy to be able to accelerate particles to the speed of light!
  7. Oct 28, 2005 #6


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    Maybe this way: If you pass a bunch of photons near a massive object (eg an atomic nucleus), it can separate into matter and antimatter.
    When you have antimatter and some advanced technology, you could build rockets which permit the highest travel speeds - but still slightly less than the speed of light.
  8. Oct 28, 2005 #7
    I had trouble identifying a questions but I suppose I could at least try to articulate some of the numerous misconceptions.
    (1) Matter and antimatter are identical except mirror images (basically).
    (2) Photons are their own antiparticle.
    (3) Antimatter does not exist in matter, titanium included. They would quickly annihilate each other.
    (4) Antimatter is created directly from energy via high speed particles collisions thanks to e=mc^2.
    (5) The only thing propelled at the speed of light is the light (mainly gamma rays) produced when matter and antimatter come in contact and annihilate each other. It would make an excellent fuel though. A few grams could in principle run your car a few hundred thousand years.
    (6) Matter and antimatter are always produced in pairs in the laboratory and must be magnetically trapped, separated, siphoned off, cooled, and contained. Well there's a few other tricks besides magnetic that can be used but that's more than I want to get into.
    Hope that helps...
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