Magnetisation and Mean Field Theory in the Ising Model

  title={Magnetisation and Mean Field Theory in the Ising Model},
  author={Dalton A R Sakthivadivel},
  journal={SciPost Physics Lecture Notes},
In this set of notes, a complete, pedagogical tutorial for applying mean field theory to the two-dimensional Ising model is presented. Beginning with the motivation and basis for mean field theory, we formally derive the Bogoliubov inequality and discuss mean field theory itself. We proceed with the use of mean field theory to determine a magnetisation function, and the results of the derivation are interpreted graphically, physically, and mathematically. We give a new interpretation of the… 
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