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Cold Fusion Questions

  1. Nov 9, 2004 #1
    I am very ignorant on this subject and was just wondering a few things.

    What exactly is it (how do they do it), I am having trouble finding information on it.

    Why cant it be recreated, or was it really done at all?

    Also I was wondering what resources it uses to create the energy.
  2. jcsd
  3. Nov 11, 2004 #2


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  4. Nov 11, 2004 #3


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    It's the consensus of physicists that it really doesn't exist.

    That's why it can't be recreated. Think about it. In order to get
    fusion, one has to get the nuclei of the atoms very close in order for
    the strong nuclear force - which is short range - to take hold and fuse
    the nuclei together and release energy.

    However, the nuclei are both positively charged - and like charges
    repel. In order to get the nuclei close enough with the electric repulsion
    trying to push them apart all the way - the nuclei have to be traveling
    fast enough so that they can overcome this repulsion.

    If the nuclei are moving fast enough to overcome this repulsion - then
    the material is hot - because that's what heat is - fast moving atoms.
    The temperatures that are high enough for the nuclei to overcome this
    electric repulsion are in the millions of degrees. The material is in a
    state of matter called a "plasma".

    I'd forget about research "cold fusion", and learn about real fusion
    research - both magnetic confinement as pursued at the Princeton
    Plasma Physics Laboratory, or inertial confinement as pursued at
    Lawrence Livermore National Laboratory, the University of Rochester,
    and other sites:






    Dr. Gregory Greenman
    Last edited: Nov 11, 2004
  5. Nov 11, 2004 #4
    Thank you very much for your information and suggestions.

    "The successful operation of a fusion power plant will require the use of materials resistant to energetic neutron bombardment, thermal stress, and magnetic forces." http://www.pppl.gov/fusion_basics/pages/fusion_power_plant.html [Broken]

    What materials are they using now, and what materials could they use?
    Last edited by a moderator: May 1, 2017
  6. Nov 11, 2004 #5


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    Right now the materials used are not important.

    The fusion experiments that PPPL does / has done - do result in the
    release of energetic neutrons - but only for a short period of time.

    Therefore, the test reactor isn't damaged by the neutrons - they don't
    bombard the structure of the test reactor long enough to cause
    significant damage.

    They are just saying that, in the future, when fusion power reactors are
    in existence - they will operate continuously - and thus sufficient
    neutron bombardment may damage reactor materials.

    This will have to be taken care of in the design of the future fusion
    reactor. For example, if energetic neutrons are a problem - for example
    the Deuterium-Tritium reaction releases 14.1 MeV neutrons - then some
    way needs to be engineered to deal with these high energy neutrons.

    Probably what one would do is to use some light isotope - like the
    hydrogen in water, or lithium to slow the neutrons down so that they
    are slow neutrons. Slow neutrons are more easily absorbed by such
    materials as cadmium and boron.

    Slowing the neutrons down is also how one would extract the fusion
    energy which is mostly in the neutrons with a D-T fusion reaction.

    One way of doing this is by using a "wall" of liquid lithium as scientists
    at Princeton are experimenting with:

    http://www.pppl.gov/publications/pics/info_bull_cdxu_0703.pdf [Broken].

    Dr. Gregory Greenman
    Last edited by a moderator: May 1, 2017
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