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Neutrons and hydrogen atoms

  1. Aug 7, 2004 #1
    A long time ago, when I did my degree I was taught that Neutrons have a half life of (about 10 minutes?). I also remember that the elementry particle equation was:

    N <-> P+e.

    Now, a proton plus an electron could look a lot like a hydrogen atom and I also remember that the electron in a hydrogen atom at it's lowest allowed energy does a figure 8 through the nucleus with a node in it's centre. The proton has a small radius, I know, but it seems like the electron would occasionally be in the proton? I am also thinking of the energy being negotiable because of the HUP.

    Now I am probably sounding confused.

    The question I would like to ask is:

    Is there a probability (perhaps a very small one) that a hydrogen atom can decay into a neutron? Why/Why not?
  2. jcsd
  3. Aug 7, 2004 #2


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    It works the other way around. A neutron can decay into a proton and an electron, plus an antineutrino, via the weak interaction. But that's not because the neutron has the proton and electron inside it; it's because the weak force can turn one kind of quark into another, and conservation of charge has to be satisfied in the cheapest way possible.
  4. Aug 7, 2004 #3
    Yeah, I think they taught me that, it was just too long ago.

    What stops the process happening in reverse?
  5. Aug 7, 2004 #4
    Happy birthday by the way. I just noticed!
  6. Aug 10, 2004 #5
    err, so is it an entropy thing then?
  7. Aug 10, 2004 #6


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    Thank you.

    The reason it doesn't run in reverse is that there isn't enough energy. The weak decay is energetically downhill,and inverse weak decay is uphill.
  8. Aug 17, 2004 #7
    Any idea how much energy?
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