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1 | (8) |
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0.1 What is quantum field theory? |
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1 | (1) |
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2 | (1) |
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0.3 Who is this book for? |
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2 | (1) |
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3 | (3) |
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6 | (1) |
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7 | (2) |
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I The Universe as a set of harmonic oscillators |
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9 | (40) |
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10 | (9) |
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10 | (1) |
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10 | (1) |
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11 | (3) |
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1.4 Lagrangians and least action |
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14 | (2) |
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16 | (3) |
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17 | (2) |
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2 Simple harmonic oscillators |
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19 | (9) |
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19 | (1) |
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19 | (4) |
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2.3 A trivial generalization |
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23 | (2) |
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25 | (3) |
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27 | (1) |
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3 Occupation number representation |
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28 | (9) |
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28 | (1) |
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3.2 Changing-the notation |
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29 | (2) |
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3.3 Replace state labels with operators |
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31 | (1) |
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3.4 Indistinguishability and symmetry |
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31 | (4) |
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35 | (2) |
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36 | (1) |
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4 Making second quantization work |
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37 | (12) |
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37 | (2) |
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4.2 How to second quantize an operator |
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39 | (4) |
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4.3 The kinetic energy and the tight-binding Hamiltonian |
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43 | (1) |
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44 | (2) |
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46 | (3) |
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48 | (1) |
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II Writing down Lagrangians |
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49 | (22) |
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50 | (9) |
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5.1 Lagrangians and Hamiltonians |
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50 | (2) |
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5.2 A charged particle in an electromagnetic field |
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52 | (2) |
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54 | (1) |
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5.4 Lagrangian and Hamiltonian density |
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55 | (4) |
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58 | (1) |
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6 A first stab at relativistic quantum mechanics |
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59 | (5) |
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6.1 The Klein-Gordon equation |
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59 | (2) |
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6.2 Probability currents and densities |
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61 | (1) |
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6.3 Feynman's interpretation of the negative energy states |
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61 | (2) |
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63 | (1) |
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63 | (1) |
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7 Examples of Lagrangians, or how to write down a theory |
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64 | (7) |
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7.1 A massless scalar field |
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64 | (1) |
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7.2 A massive scalar field |
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65 | (1) |
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66 | (1) |
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67 | (1) |
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67 | (1) |
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7.6 The complex scalar field |
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68 | (3) |
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69 | (2) |
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III The need for quantum fields |
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71 | (72) |
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72 | (7) |
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8.1 Schrodinger's picture and the time-evolution operator |
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72 | (2) |
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8.2 The Heisenberg picture |
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74 | (1) |
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8.3 The death of single-particle quantum mechanics |
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75 | (1) |
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8.4 Old quantum theory is dead; long live fields! |
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76 | (3) |
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78 | (1) |
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9 Quantum mechanical transformations |
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79 | (11) |
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9.1 Translations in spacetime |
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79 | (3) |
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82 | (1) |
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9.3 Representations of transformations |
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83 | (2) |
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9.4 Transformations of quantum fields |
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85 | (1) |
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9.5 Lorentz transformations |
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86 | (4) |
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88 | (2) |
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90 | (8) |
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10.1 Invariance and conservation |
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90 | (2) |
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92 | (2) |
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10.3 Spacetime translation |
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94 | (2) |
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96 | (2) |
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97 | (1) |
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11 Canonical quantization of fields |
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98 | (11) |
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11.1 The canonical quantization machine |
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98 | (3) |
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101 | (1) |
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11.3 What becomes of the Hamiltonian? |
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102 | (2) |
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104 | (2) |
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11.5 The meaning of the mode expansion |
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106 | (3) |
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108 | (1) |
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12 Examples of canonical quantization |
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109 | (8) |
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12.1 Complex scalar field theory |
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109 | (2) |
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12.2 Noether's current for complex scalar field theory |
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111 | (1) |
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12.3 Complex scalar field theory in the non-relativistic limit |
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112 | (5) |
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116 | (1) |
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13 Fields with many components and massive electromagnetism |
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117 | (9) |
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117 | (3) |
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13.2 Massive electromagnetism |
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120 | (3) |
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13.3 Polarizations and projections |
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123 | (3) |
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125 | (1) |
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14 Gauge fields and gauge theory |
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126 | (9) |
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14.1 What is a gauge field? |
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126 | (3) |
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14.2 Electromagnetism is the simplest gauge theory |
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129 | (2) |
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14.3 Canonical quantization of the electromagnetic field |
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131 | (4) |
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134 | (1) |
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15 Discrete transformations |
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135 | (8) |
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135 | (1) |
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136 | (1) |
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137 | (2) |
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15.4 Combinations of discrete and continuous transformations |
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139 | (4) |
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142 | (1) |
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IV Propagators and perturbations |
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143 | (52) |
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16 Propagators and Green's functions |
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144 | (10) |
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16.1 What is a Green's function? |
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144 | (2) |
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16.2 Propagators in quantum mechanics |
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146 | (3) |
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16.3 Turning it around: quantum mechanics from the propagator and a first look at perturbation theory |
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149 | (2) |
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16.4 The many faces of the propagator |
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151 | (3) |
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152 | (2) |
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17 Propagators and fields |
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154 | (11) |
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17.1 The field propagator in outline |
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155 | (1) |
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17.2 The Feynman propagator |
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156 | (2) |
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17.3 Finding the free propagator for scalar field theory |
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158 | (1) |
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17.4 Yukawa's force-carrying particles |
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159 | (3) |
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17.5 Anatomy of the propagator |
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162 | (3) |
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163 | (2) |
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165 | (10) |
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18.1 The 5-matrix: a hero for our times |
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166 | (1) |
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18.2 Some new machinery: the interaction representation |
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167 | (1) |
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18.3 The interaction picture applied to scattering |
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168 | (1) |
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18.4 Perturbation expansion of the 5-matrix |
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169 | (2) |
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171 | (4) |
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174 | (1) |
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19 Expanding the 5-matrix: Feynman diagrams |
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175 | (13) |
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19.1 Meet some interactions |
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176 | (1) |
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19.2 The example of φ4 theory |
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177 | (4) |
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19.3 Anatomy of a diagram |
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181 | (1) |
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182 | (1) |
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19.5 Calculations in p-space |
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183 | (3) |
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19.6 A first look at scattering |
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186 | (2) |
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187 | (1) |
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188 | (7) |
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20.1 Another theory: Yukawa's ψ† ψφ interactions |
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188 | (2) |
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20.2 Scattering in the ψ† ψφ theory |
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190 | (2) |
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20.3 The transition matrix and the invariant amplitude |
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192 | (1) |
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20.4 The scattering cross-section |
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193 | (2) |
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194 | (1) |
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V Interlude: wisdom from statistical physics |
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195 | (14) |
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21 Statistical physics: a crash course |
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196 | (5) |
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21.1 Statistical mechanics in a nutshell |
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196 | (1) |
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21.2 Sources in statistical physics |
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197 | (1) |
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198 | (3) |
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199 | (2) |
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22 The generating functional for fields |
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201 | (8) |
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22.1 How to find Green's functions |
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201 | (2) |
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22.2 Linking things up with the Gell-Mann-Low theorem |
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203 | (1) |
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22.3 How to calculate Green's functions with diagrams |
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204 | (2) |
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22.4 More facts about diagrams |
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206 | (3) |
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208 | (1) |
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209 | (50) |
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23 Path integrals: I said to him, `You're crazy' |
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210 | (11) |
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23.1 How to do quantum mechanics using path integrals |
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210 | (3) |
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23.2 The Gaussian integral |
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213 | (4) |
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23.3 The propagator for the simple harmonic oscillator |
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217 | (4) |
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220 | (1) |
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221 | (7) |
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24.1 The functional integral for fields |
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221 | (1) |
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24.2 Which field integrals should you do? |
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222 | (1) |
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24.3 The generating functional for scalar fields |
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223 | (5) |
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226 | (2) |
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25 Statistical field theory |
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228 | (9) |
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25.1 Wick rotation and Euclidean space |
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229 | (2) |
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25.2 The partition function |
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231 | (2) |
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25.3 Perturbation theory and Feynman rules |
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233 | (4) |
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236 | (1) |
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237 | (10) |
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237 | (2) |
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26.2 Breaking symmetry with a Lagrangian |
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239 | (1) |
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26.3 Breaking a continuous symmetry: Goldstone modes |
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240 | (2) |
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26.4 Breaking a symmetry in a gauge theory |
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242 | (2) |
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26.5 Order in reduced dimensions |
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244 | (3) |
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245 | (2) |
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247 | (8) |
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27.1 Coherent states of the harmonic oscillator |
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247 | (2) |
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27.2 What do coherent states look like? |
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249 | (1) |
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27.3 Number, phase and the phase operator |
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250 | (2) |
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27.4 Examples of coherent States |
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252 | (3) |
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253 | (2) |
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28 Grassmann numbers: coherent states and the path integral for fermions |
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255 | (4) |
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255 | (2) |
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28.2 Coherentstates for fermions |
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257 | (1) |
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28.3 The path integral for fermions |
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257 | (2) |
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258 | (1) |
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259 | (14) |
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260 | (7) |
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260 | (2) |
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262 | (2) |
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264 | (3) |
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266 | (1) |
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30 Topological field theory |
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267 | (6) |
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30.1 Fractional statistics a la Wilczek: the strange case of anyons |
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267 | (2) |
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269 | (2) |
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30.3 Fractional statistics from Chern-Simons theory |
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271 | (2) |
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272 | (1) |
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VIII Renormalization: taming the infinite |
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273 | (48) |
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31 Renormalization, quasiparticles and the Fermi surface |
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274 | (11) |
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31.1 Recap: interacting and non-interacting theories |
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274 | (2) |
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276 | (1) |
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31.3 The propagator for a dressed particle |
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277 | (2) |
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31.4 Elementary quasiparticles in a metal |
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279 | (1) |
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31.5 The Landau Fermi liquid |
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280 | (5) |
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284 | (1) |
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32 Renormalization: the problem and its solution |
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285 | (10) |
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32.1 The problem is divergences |
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285 | (2) |
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32.2 The solution is counterterms |
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287 | (1) |
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32.3 How to tame an integral |
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288 | (2) |
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32.4 What counterterms mean |
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290 | (2) |
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32.5 Making renormalization even simpler |
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292 | (1) |
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32.6 Which theories are renormalizable? |
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293 | (2) |
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294 | (1) |
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33 Renormalization in action: propagators and Feynman diagrams |
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295 | (7) |
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33.1 How interactions change the propagator in perturbation theory |
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295 | (2) |
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33.2 The role of counterterms: renormalization conditions |
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297 | (1) |
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298 | (4) |
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300 | (2) |
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34 The renormalization group |
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302 | (11) |
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302 | (2) |
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34.2 Flows in parameter space |
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304 | (1) |
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34.3 The renormalization group method |
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305 | (2) |
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34.4 Application 1: asymptotic freedom |
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307 | (1) |
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34.5 Application 2: Anderson localization |
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308 | (1) |
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34.6 Application 3: the Kosterlitz-Thouless transition |
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309 | (4) |
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312 | (1) |
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35 Ferromagnetism: a renormalization group tutorial |
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313 | (8) |
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35.1 Background: critical phenomena and scaling |
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313 | (2) |
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35.2 The ferromagnetic transition and critical phenomena |
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315 | (6) |
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320 | (1) |
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321 | (48) |
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322 | (14) |
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322 | (1) |
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36.2 Massless particles: left- and right-handed wave functions |
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323 | (4) |
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36.3 Dirac and Weyl spinors |
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327 | (3) |
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36.4 Basis states for superpositions |
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330 | (2) |
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36.5 The non-relativistic limit of the Dirac equation |
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332 | (4) |
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334 | (2) |
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37 How to transform a spinor |
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336 | (5) |
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37.1 Spinors aren't vectors |
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336 | (1) |
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337 | (1) |
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337 | (2) |
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37.4 Why are there four components in the Dirac equation? |
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339 | (2) |
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340 | (1) |
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38 The quantum Dirac field |
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341 | (7) |
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38.1 Canonical quantization and Noether current |
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341 | (2) |
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38.2 The fermion propagator |
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343 | (2) |
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38.3 Feynman rules and scattering |
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345 | (1) |
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38.4 Local symmetry and a gauge theory for fermions |
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346 | (2) |
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347 | (1) |
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39 A rough guide to quantum electrodynamics |
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348 | (7) |
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39.1 Quantum light and the photon propagator |
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348 | (1) |
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39.2 Feynman rules and a first QED process |
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349 | (2) |
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39.3 Gauge invariance in QED |
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351 | (4) |
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353 | (2) |
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40 QED scattering: three famous cross-sections |
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355 | (5) |
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40.1 Example 1: Rutherford scattering |
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355 | (1) |
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40.2 Example 2: Spin sums and the Mott formula |
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356 | (1) |
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40.3 Example 3: Compton scattering |
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357 | (1) |
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358 | (2) |
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359 | (1) |
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41 The renormalization of QED and two great results |
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360 | (9) |
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41.1 Renormalizing the photon propagator: dielectric vacuum |
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361 | (3) |
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41.2 The renormalization group and the electric charge |
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364 | (1) |
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41.3 Vertex corrections and the electron g-factor |
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365 | (4) |
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368 | (1) |
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X Some applications from the world of condensed matter |
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369 | (54) |
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370 | (10) |
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42.1 Bogoliubov's hunting license |
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370 | (2) |
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42.2 Bogoliubov's transformation |
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372 | (2) |
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42.3 Superfluids and fields |
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374 | (3) |
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42.4 The current in a superfluid |
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377 | (3) |
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379 | (1) |
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43 The many-body problem and the metal |
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380 | (20) |
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380 | (3) |
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43.2 The Hartree-Fock ground state energy of a metal |
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383 | (3) |
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43.3 Excitations in the mean-field approximation |
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386 | (2) |
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388 | (1) |
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43.5 Finding the excitations with propagators |
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389 | (1) |
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43.6 Ground states and excitations |
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390 | (3) |
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43.7 The random phase approximation |
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393 | (7) |
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398 | (2) |
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400 | (11) |
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44.1 A model of a superconductor |
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400 | (2) |
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44.2 The ground state is made of Cooper pairs |
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402 | (1) |
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403 | (2) |
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44.4 The quasiparticles are bogolons |
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405 | (1) |
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406 | (1) |
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44.6 Field theory of a charged superfluid |
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407 | (4) |
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409 | (2) |
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45 The fractional quantum Hall fluid |
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411 | (12) |
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45.1 Magnetic translations |
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411 | (2) |
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413 | (2) |
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45.3 The integer quantum Hall effect |
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415 | (2) |
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45.4 The fractional quantum Hall effect |
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417 | (6) |
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421 | (2) |
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XI Some applications from the world of particle physics |
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423 | (44) |
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46 Non-abelian gauge theory |
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424 | (9) |
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46.1 Abelian gauge theory revisited |
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424 | (1) |
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425 | (3) |
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46.3 Interactions and dynamics of Wμ |
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428 | (2) |
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46.4 Breaking symmetry with a non-abelian gauge theory |
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430 | (3) |
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432 | (1) |
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47 The Weinberg-Salam model |
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433 | (11) |
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47.1 The symmetries of Nature before symmetry breaking |
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434 | (3) |
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47.2 Introducing the. Higgs field |
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437 | (1) |
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47.3 Symmetry breaking the Higgs field |
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438 | (1) |
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47.4 The origin of electron mass |
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439 | (1) |
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47.5 The photon and the gauge bosons |
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440 | (4) |
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443 | (1) |
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444 | (7) |
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48.1 The Majorana solution |
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444 | (2) |
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446 | (1) |
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48.3 Majorana mass and charge |
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447 | (4) |
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450 | (1) |
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451 | (6) |
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49.1 Dirac's monopole and the Dirac string |
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451 | (2) |
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49.2 The 't Hooft-Polyakov monopole |
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453 | (4) |
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456 | (1) |
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50 Instantons, tunnelling and the end of the world |
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457 | (10) |
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50.1 Instantons in quantum particle mechanics |
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458 | (1) |
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50.2 A particle in a potential well |
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459 | (1) |
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50.3 A particle in a double well |
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460 | (3) |
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50.4 The fate of the false vacuum |
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463 | (4) |
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466 | (1) |
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467 | (6) |
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B Useful complex analysis |
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473 | (7) |
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B.1 What is an analytic function? |
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473 | (1) |
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474 | (1) |
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B.3 How to find a residue |
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474 | (1) |
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B.4 Three rules of contour integrals |
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475 | (2) |
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B.5 What is a branch cut? |
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477 | (1) |
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B.6 The principal value of an integral |
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478 | (2) |
Index |
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480 | |