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Ising model

  1. Dec 2, 2011 #1
    One line between (+-). Two lines between (++). Zero line between (--). [tex]\gamma[/tex] number of nearest neighbours. Why we have relation

    [tex]\gamma N_+=2N_{++}+N_{+-}[/tex]

    Why we get this? Some explanation. This is from Kerson Huang.

    Attached Files:

  2. jcsd
  3. Nov 4, 2013 #2
    Choose a + site. Join it to each neighbor by a line. we need to draw gamma lines. Now do this for all + sites. So total lines = gamma*N(+). In this process i) between any (+,+) pair there will be two lines (one when we draw line from 1st + to 2nd +, other when we draw line from 2nd + to 1st +). Now there are N(++) number of (+,+) pair. So total lines between all (+,+) pair is 2N(++).. ii) between any (+,-) pair there will be one line (when drawn from + to -). There are N(+-) number of (+,-) pair. iii) between any (-,-) pair there will be no line. So total lines = 2N(++) + N(+-).
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