Preface |
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v | |
About the Author |
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xi | |
1 The Methodology of Statistical Mechanics |
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1 | (60) |
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1.1 Terminology and Methodology |
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1 | (3) |
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1.1.1 Approaches to the subject |
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1 | (2) |
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1.1.2 Description of states |
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3 | (1) |
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1.1.3 Extensivity and the thermodynamic limit |
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3 | (1) |
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1.2 The Fundamental Principles |
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4 | (4) |
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1.2.1 The laws of thermodynamics |
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4 | (2) |
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1.2.2 Probabilistic interpretation of the First Law |
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6 | (1) |
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1.2.3 Microscopic basis for entropy |
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7 | (1) |
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1.3 Interactions - The Conditions for Equilibrium |
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8 | (10) |
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1.3.1 Thermal interaction - Temperature |
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8 | (3) |
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1.3.2 Volume change - Pressure |
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11 | (2) |
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1.3.3 Particle interchange - Chemical potential |
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13 | (1) |
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1.3.4 Thermal interaction with the rest of the world - The Boltzmann factor |
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14 | (2) |
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1.3.5 Particle and energy exchange with the rest of the world - The Gibbs factor |
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16 | (2) |
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1.4 Thermodynamic Averages |
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18 | (11) |
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1.4.1 The partition function |
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18 | (1) |
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1.4.2 Gibbs expression for entropy |
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19 | (2) |
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21 | (1) |
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1.4.4 Thermodynamic variables |
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22 | (1) |
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23 | (1) |
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24 | (2) |
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1.4.7 The grand partition function |
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26 | (1) |
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1.4.8 The grand potential |
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27 | (1) |
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1.4.9 Thermodynamic variables |
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28 | (1) |
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1.5 Quantum Distributions |
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29 | (6) |
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1.5.1 Bosons and Fermions |
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29 | (3) |
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1.5.2 Grand potential for identical particles |
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32 | (1) |
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1.5.3 The Fermi-Dirac distribution |
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33 | (1) |
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1.5.4 The Bose-Einstein distribution |
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34 | (1) |
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1.5.5 The classical limit - The Maxwell-Boltzmann distribution |
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34 | (1) |
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1.6 Classical Statistical Mechanics |
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35 | (11) |
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1.6.1 Phase space and classical states |
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35 | (2) |
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1.6.2 Boltzmann and Gibbs phase spaces |
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37 | (1) |
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1.6.3 The Fundamental Postulate in the classical case |
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38 | (1) |
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1.6.4 The classical partition function |
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39 | (1) |
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1.6.5 The equipartition theorem |
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39 | (2) |
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1.6.6 Consequences of equipartition |
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41 | (2) |
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1.6.7 Liouville's theorem |
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43 | (2) |
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1.6.8 Boltzmann's H theorem |
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45 | (1) |
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1.7 The Third Law of Thermodynamics |
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46 | (9) |
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1.7.1 History of the Third Law |
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46 | (1) |
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47 | (1) |
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48 | (2) |
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1.7.4 Unattainability of absolute zero |
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50 | (1) |
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1.7.5 Heat capacity at low temperatures |
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51 | (1) |
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1.7.6 Other consequences of the Third Law |
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52 | (3) |
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1.7.7 Pessimist's statement of the laws of thermodynamics |
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55 | (1) |
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55 | (3) |
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58 | (3) |
2 Practical Calculations with Ideal Systems |
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61 | (88) |
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2.1 The Density of States |
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61 | (7) |
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2.1.1 Non-interacting systems |
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61 | (1) |
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2.1.2 Converting sums to integrals |
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62 | (1) |
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2.1.3 Enumeration of states |
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62 | (2) |
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64 | (1) |
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2.1.5 General expression for the density of states |
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65 | (2) |
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2.1.6 Relation between pressure and energy |
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67 | (1) |
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68 | (2) |
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2.2.1 Indistinguishability |
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68 | (1) |
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2.2.2 Classical approximation |
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69 | (1) |
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70 | (8) |
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70 | (2) |
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72 | (1) |
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2.3.3 Thermodynamic properties |
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72 | (2) |
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2.3.4 The 1/N! term in the partition function |
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74 | (1) |
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75 | (3) |
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78 | (1) |
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2.4.1 Methodology for quantum gases |
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78 | (1) |
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2.5 Fermi Gas at Low Temperatures |
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79 | (16) |
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2.5.1 Ideal Fermi gas at zero temperature |
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79 | (3) |
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2.5.2 Fermi gas at low temperatures - Simple model |
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82 | (3) |
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2.5.3 Fermi gas at low temperatures - Series expansion |
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85 | (7) |
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2.5.4 More general treatment of low-temperature heat capacity |
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92 | (3) |
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2.6 Bose Gas at Low Temperatures |
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95 | (13) |
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2.6.1 General procedure for treating the Bose gas |
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95 | (1) |
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2.6.2 Ground state occupation - Chemical potential |
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96 | (1) |
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2.6.3 Number of particles |
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97 | (1) |
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2.6.4 Low-temperature behaviour of Bose gas |
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97 | (4) |
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2.6.5 Heat capacity of Bose gas |
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101 | (3) |
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2.6.6 Comparison with superfluid 4He |
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104 | (1) |
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2.6.7 Two-fluid model of superfluid 4He |
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105 | (1) |
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2.6.8 Elementary excitations |
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106 | (2) |
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2.7 Quantum Gas at High Temperatures - The Classical Limit |
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108 | (5) |
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2.7.1 General treatment for Fermi, Bose and Maxwell cases |
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108 | (1) |
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2.7.2 Quantum energy parameter |
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109 | (1) |
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110 | (1) |
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111 | (1) |
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112 | (1) |
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2.8 Gas in a Harmonic Trap |
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113 | (8) |
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2.8.1 Enumeration and counting of states |
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113 | (2) |
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2.8.2 Trapped bosons at low temperatures - Bose- Einstein condensation |
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115 | (6) |
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2.9 Black Body Radiation - The Photon Gas |
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121 | (8) |
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2.9.1 Photons as quantised electromagnetic waves |
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121 | (1) |
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2.9.2 Photons in thermal equilibrium - Black body radiation |
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122 | (1) |
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123 | (2) |
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2.9.4 Internal energy and heat capacity |
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125 | (2) |
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2.9.5 Black body radiation in one dimension - Johnson noise |
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127 | (2) |
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129 | (10) |
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2.10.1 Partition function and free energy |
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129 | (1) |
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2.10.2 Thermodynamic properties |
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130 | (4) |
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2.10.3 Negative temperatures |
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134 | (2) |
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2.10.4 Thermodynamics of negative temperatures |
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136 | (3) |
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139 | (7) |
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146 | (3) |
3 Non-ideal Gases |
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149 | (54) |
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3.1 Statistical Mechanics of Interacting Particles |
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149 | (5) |
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3.1.1 The partition function |
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149 | (1) |
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150 | (2) |
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3.1.3 Low-density approximation |
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152 | (1) |
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153 | (1) |
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154 | (20) |
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3.2.1 Virial coefficients |
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154 | (1) |
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3.2.2 Hard-core potential |
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154 | (3) |
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3.2.3 Square-well potential |
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157 | (2) |
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3.2.4 Lennard-Jones potential |
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159 | (3) |
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3.2.5 The Sutherland potential |
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162 | (3) |
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3.2.6 Comparison of models |
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165 | (2) |
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3.2.7 Universal behaviour |
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167 | (1) |
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3.2.8 Quantum gases - The special case(s) of helium |
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168 | (6) |
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174 | (4) |
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174 | (1) |
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3.3.2 Joule-Kelvin coefficient |
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175 | (1) |
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3.3.3 Connection with the second virial coefficient |
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176 | (1) |
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3.3.4 Inversion temperature |
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177 | (1) |
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3.4 Van der Waals Equation of State |
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178 | (4) |
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3.4.1 Approximating the partition function |
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178 | (1) |
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3.4.2 Van der Waals equation |
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179 | (1) |
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3.4.3 Estimation of van der Waals parameters |
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180 | (2) |
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182 | (1) |
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3.5 Other Phenomenological Equations of State |
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182 | (3) |
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3.5.1 The Dieterici equation |
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182 | (2) |
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3.5.2 The Berthelot equation |
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184 | (1) |
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3.5.3 The Redlich-Kwong equation |
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184 | (1) |
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185 | (10) |
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3.6.1 Possible approaches |
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185 | (1) |
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3.6.2 Hard-sphere equation of state |
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186 | (2) |
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188 | (1) |
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3.6.4 Virial coefficients |
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188 | (1) |
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3.6.5 Carnahan and Starling procedure |
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189 | (3) |
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192 | (3) |
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195 | (5) |
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200 | (3) |
4 Phase Transitions |
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203 | (110) |
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203 | (16) |
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203 | (2) |
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205 | (2) |
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207 | (1) |
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4.1.4 Order of phase transitions |
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208 | (1) |
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4.1.5 The order parameter |
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209 | (2) |
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4.1.6 Conserved and non-conserved order parameters |
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211 | (1) |
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212 | (2) |
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4.1.8 The scaling hypothesis |
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214 | (4) |
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4.1.9 Scaling of the free energy |
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218 | (1) |
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4.2 First-Order Transition - An Example |
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219 | (13) |
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219 | (3) |
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4.2.2 Van der Waals fluid |
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222 | (1) |
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4.2.3 The Maxwell construction |
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223 | (3) |
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226 | (1) |
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4.2.5 Corresponding states |
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226 | (3) |
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4.2.6 Dieterici's equation |
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229 | (1) |
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4.2.7 Quantum mechanical effects |
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230 | (2) |
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4.3 Second-Order Transition - An Example |
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232 | (11) |
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232 | (1) |
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233 | (3) |
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4.3.3 Spontaneous magnetisation |
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236 | (2) |
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238 | (1) |
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4.3.5 Magnetic susceptibility |
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239 | (2) |
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4.3.6 The ground state and Goldstone modes |
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241 | (2) |
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4.4 The Ising and Other Models |
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243 | (11) |
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4.4.1 Ubiquity of the Ising model |
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243 | (2) |
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4.4.2 Magnetic case of the Ising model |
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245 | (2) |
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4.4.3 Ising model in one dimension |
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247 | (1) |
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4.4.4 Ising model in two dimensions |
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248 | (3) |
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4.4.5 Mean field critical exponents |
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251 | (2) |
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253 | (1) |
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4.4.7 The spherical model |
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254 | (1) |
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4.5 Landau Theory of Phase Transitions |
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254 | (10) |
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254 | (1) |
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4.5.2 Landau free energy for the ferromagnet |
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255 | (4) |
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4.5.3 Landau theory - Second-order transitions |
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259 | (2) |
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4.5.4 Heat capacity in the Landau model |
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261 | (1) |
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4.5.5 Ferromagnet in a magnetic field |
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262 | (2) |
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264 | (10) |
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4.6.1 Description of the phenomenon |
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264 | (1) |
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265 | (2) |
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267 | (1) |
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268 | (4) |
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4.6.5 Entropy and latent heat at the transition |
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272 | (1) |
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273 | (1) |
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274 | (16) |
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274 | (1) |
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275 | (1) |
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276 | (1) |
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277 | (1) |
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278 | (1) |
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4.7.6 Phase separation - The lever rule |
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279 | (1) |
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4.7.7 Phase separation curve - The binodal |
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280 | (3) |
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283 | (1) |
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4.7.9 Entropy in the ordered phase |
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284 | (2) |
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4.7.10 Heat capacity in the ordered phase |
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286 | (1) |
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4.7.11 Order of the transition and the critical point |
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287 | (2) |
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4.7.12 The critical exponent p |
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289 | (1) |
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4.8 Quantum Phase Transitions |
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290 | (10) |
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290 | (1) |
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4.8.2 The transverse Ising model |
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291 | (1) |
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4.8.3 Recap of mean field Ising model |
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292 | (2) |
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4.8.4 Application of a transverse field |
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294 | (2) |
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4.8.5 Transition temperature |
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296 | (1) |
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4.8.6 Quantum critical behaviour |
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297 | (1) |
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4.8.7 Dimensionality and critical exponents |
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298 | (2) |
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300 | (5) |
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4.9.1 The existence of order |
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300 | (1) |
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4.9.2 Validity of mean field theory |
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301 | (1) |
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4.9.3 Universality classes |
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302 | (2) |
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4.9.4 Features of different phase transition models |
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304 | (1) |
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305 | (4) |
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309 | (4) |
5 Fluctuations and Dynamics |
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313 | (62) |
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314 | (12) |
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5.1.1 Probability distribution functions |
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314 | (2) |
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5.1.2 Average behaviour of fluctuations |
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316 | (5) |
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5.1.3 The autocorrelation function |
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321 | (2) |
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5.1.4 The correlation time |
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323 | (1) |
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5.1.5 Spectral density - The Wiener-Khintchine theorem |
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324 | (2) |
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326 | (6) |
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5.2.1 Kinematics of a Brownian particle |
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327 | (2) |
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329 | (1) |
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330 | (1) |
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331 | (1) |
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332 | (12) |
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332 | (1) |
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5.3.2 Separation of forces |
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333 | (2) |
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5.3.3 The Langevin equation |
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335 | (1) |
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5.3.4 Velocity autocorrelation function |
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336 | (1) |
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5.3.5 Mean-square velocity and equipartition |
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337 | (1) |
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5.3.6 Diffusion coefficient |
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338 | (1) |
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5.3.7 Harmonically bound particle |
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339 | (2) |
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5.3.8 Equipartition and mean-square values |
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341 | (2) |
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5.3.9 Electrical analogue of the Langevin equation |
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343 | (1) |
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5.4 Linear Response I - Phenomenology |
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344 | (17) |
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5.4.1 Definitions and assumptions |
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344 | (2) |
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5.4.2 Response to a harmonic excitation |
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346 | (3) |
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5.4.3 Fourier representation |
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349 | (1) |
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5.4.4 Response to a step excitation |
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350 | (1) |
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5.4.5 Response to a "shock" or delta function excitation |
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351 | (1) |
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5.4.6 Response to a noise excitation |
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352 | (2) |
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5.4.7 Consequence of the reality of X(t) |
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354 | (1) |
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5.4.8 Consequence of causality |
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355 | (2) |
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5.4.9 Energy considerations |
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357 | (2) |
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5.4.10 Static susceptibility |
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359 | (1) |
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5.4.11 Relaxation time approximation |
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360 | (1) |
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5.5 Linear Response II - Microscopics |
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361 | (7) |
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5.5.1 Onsager's hypothesis |
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361 | (2) |
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363 | (2) |
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5.5.3 Calculation of the step response function |
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365 | (2) |
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5.5.4 Calculation of the autocorrelation function |
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367 | (1) |
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368 | (4) |
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372 | (3) |
Appendix A The Gibbs-Duhem Relation |
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375 | (4) |
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A.1 Homogeneity of the Fundamental Relation |
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375 | (1) |
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375 | (1) |
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376 | (1) |
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A.4 The Gibbs-Duhem Relation |
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376 | (3) |
Appendix B Thermodynamic Potentials |
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379 | (8) |
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379 | (2) |
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B.2 Constant Temperature and Volume: The Helmholtz Potential |
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381 | (1) |
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B.3 Constant Pressure and Energy: The Enthalpy Function |
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382 | (1) |
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B.4 Constant Pressure and Temperature: The Gibbs Free Energy |
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383 | (1) |
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B.5 Differential Expressions for the Potentials |
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384 | (1) |
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B.6 Natural Variables and the Maxwell Relations |
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384 | (3) |
Appendix C Mathematica Notebooks |
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387 | (22) |
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C.1 Chemical Potential of a Fermi Gas at Low Temperatures - Sommerfeld Expansion |
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387 | (3) |
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C.1.1 Setting up the problem |
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387 | (1) |
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C.1.2 Mathematica manipulations |
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388 | (2) |
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C.2 Internal Energy of a Fermi Gas at Low Temperatures - Sommerfeld Expansion |
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390 | (2) |
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C.2.1 Setting up the problem |
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390 | (1) |
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C.2.2 Mathematica manipulations |
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391 | (1) |
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C.3 Fugacity and Chemical Potential of the Fermi, Bose, and Maxwell Gas at High Temperatures |
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392 | (4) |
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C.3.1 Setting up the problem |
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392 | (1) |
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C.3.2 Mathematica manipulations |
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393 | (3) |
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C.4 Internal Energy of the Fermi, Bose, and Maxwell Gas at High Temperatures |
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396 | (3) |
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C.4.1 Setting up the problem |
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396 | (1) |
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C.4.2 Mathematica manipulations |
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397 | (2) |
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C.5 Chemical Potential of the Bose Gas at Low Temperatures |
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399 | (4) |
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C.5.1 Setting up the problem |
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399 | (1) |
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C.5.2 Mathematica manipulations |
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400 | (3) |
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C.6 Internal Energy (and Heat Capacity) of the Bose Gas at Low Temperatures |
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403 | (6) |
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C.6.1 Setting up the problem |
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403 | (1) |
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C.6.2 Mathematica manipulations |
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404 | (5) |
Appendix D Evaluation of the Correlation Function Integral |
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409 | (4) |
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D.1 Initial Domain of Integration |
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409 | (1) |
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D.2 Transformation of Variables |
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410 | (1) |
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D.3 Jacobian of the Transformation |
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411 | (2) |
Appendix E Bose-Einstein and Fermi-Dirac Distribution Functions |
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413 | (4) |
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413 | (3) |
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416 | (1) |
References |
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417 | (2) |
Index |
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419 | |