Applications of Combinatorial Analysis to the Calculation of the Partition Function of the Ising Model

Author: Lin, Ming-Shr Matt

Year: 2009

Degree: Dissertation (Ph.D.)

Advisor: Wilson, Richard M.

Committee Members: Wilson, Richard M.; Wales, David B.; Preskill, John P.; Cross, Michael Clifford

Option: Physics; Business Economics and Management; Electrical Engineering

DOI: 10.7907/RSXD-6W47

Abstract

The research work discussed in this thesis investigated the application of combinatorics and graph theory in the analysis of the partition function of the Ising Model.

Chapter 1 gives a general introduction to the partition function of the Ising Model and the Feynman Identity in the language of graph theory.

Chapter 2 describes and proves combinatorially the Feynman Identity in the special case when there is only one vertex and multiple loops.

Chapter 3 digresses into the number of cycles in a directed graph, along with its application in the special case to derive the analytical expression of the number of non-periodic cycles with positive and negative signs.

Chapter 4 comes back to the general case of the Feynman Identity. The Feynman Identity is applied to several special cases of the graph and a combinatorial identity is established for each case.

Chapter 5 concludes the thesis by summarizing the main ideas in each chapter.

Files