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Coherent Control of Fusion?

  1. Jul 9, 2015 #1
    http://www.iflscience.com/space/molecules-have-been-built-using-laser-beam-first-time [Broken]

    Is there a way that fusion could be achieved with coherent control like this? If it can build molecules couldnt deuterium-deuterium be achieved?
    Last edited by a moderator: May 7, 2017
  2. jcsd
  3. Jul 9, 2015 #2


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    I don't see how. Inertial confinement fusion (which is laser-driven) involves pouring huge amounts of energy into a small fuel pellet in a tiny fraction of a second. It is wildly different than using a laser to bond atoms and molecules together.
  4. Jul 9, 2015 #3
    If the lasers can build molecules why can they bond deuterium together?
  5. Jul 9, 2015 #4


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    The problem is one of numbers.
    Getting a few molecules to fuse is not that much of a problem, but the difficulty escalates as the numbers increase, sort of a 'herding cats' phenomenon.
    To get useful amounts of power, we need lots of molecules fusing, not just a few million.
  6. Jul 9, 2015 #5


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    Certainly one can create diatomic molecules of deuterium. That does not grant fusion.

    In fusion, the nuclei must fuse by overcoming the Coulomb repulsion until the nuclear force takes over. The idea of heating a plasma is to allow the nuclei to approach each other that the nuclei can fuse, reform and release energy (transform binding energy into kinetic energy).
  7. Jul 9, 2015 #6


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    I'm not sure you understand how fusion works. These lasers are building chemical bonds between atoms - which have eV energy scales. Fusion involves two atomic nuclei coming together to produce a new nucleus. It is a nuclear process, and you need nuclear energy scales - MeV.
  8. Jul 9, 2015 #7


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    Because the energy required to overcome nuclear coulomb forces is on the order of a million times greater than that required to overcome molecular forces.
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