1. PF Contest - Win "Conquering the Physics GRE" book! Click Here to Enter
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Ground state hydrogen parallel to the double slit experiment?

  1. May 30, 2010 #1
    In the double slit experiment the electron can go through either slit. As long as it is not observed there is an interference pattern as the two possibilities superimpose. The common conclusion to this is that the electron goes through both slits.

    Is there a parallel with the ground state of hydrogen? One electron has two states it can be in - spin up/spin down. Does this mean the wave functions for both situations superimpose and it is in both states at once as long as it is not observed (giving a spin of zero!!)

    I'm sure the answer to this is an abrupt and sharp 'No' but I was wondering why not.
  2. jcsd
  3. May 30, 2010 #2


    User Avatar
    Science Advisor

  4. May 30, 2010 #3
    Oh right! So is it pushing it to say the electron has/can have zero spin?

    Answers need not be restricted to the quantum states of 'thumbs up' ('yes') or 'thumbs down' ('no') :biggrin:
  5. May 30, 2010 #4


    User Avatar
    Science Advisor


    Consider for simplicity a state of the hydrogen atom of the form

    [tex]|nlms\rangle = |nlm\rangle \frac{1}{\sqrt{2}}\left(|s=+1/2\rangle - |s=-1/2\rangle\right)[/tex]

    So the electron does not have zero spin, but it is in a state with zero expectation value. As there is no reason why the electron should have one specific spin eigenvalue, it is in a superposition of both states.

    [tex]\langle nlms|\hat{S}_z|nlms\rangle = 0[/tex]
    Last edited: May 30, 2010
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Threads - Ground state hydrogen Date
I Why drop the vibrational ground state energy Oct 27, 2017
Can there be multiple ground states? Mar 25, 2014
Ground state Feb 6, 2014
0 entropy of ground state Oct 15, 2013
Does Light have a Ground State ? May 3, 2004