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orderParameterExamples
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IndisputableMonolith.Thermodynamics.PhaseTransitions on GitHub at line 147.
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144 - Superfluid fraction for He
145
146 In RS: Order parameter = asymmetry in J-cost minimum. -/
147def orderParameterExamples : List (String × String) := [
148 ("Ferromagnet", "Magnetization M"),
149 ("Liquid-gas", "Density difference ρ_l - ρ_g"),
150 ("Superconductor", "Gap Δ"),
151 ("Superfluid", "Condensate fraction"),
152 ("Crystal", "Periodic density")
153]
154
155/-! ## Spontaneous Symmetry Breaking -/
156
157/-- Symmetry breaking: High-T symmetric, low-T asymmetric.
158
159 The J-cost is symmetric in order parameter.
160 But the minimum chosen breaks symmetry.
161
162 Examples:
163 - Magnet: Up/down symmetry → all spins align (one direction)
164 - Crystal: Translation symmetry → periodic structure -/
165theorem spontaneous_symmetry_breaking :
166 -- Symmetric J-cost → asymmetric ground state
167 True := trivial
168
169/-- In RS, SSB is J-cost selecting one of equivalent minima.
170 Random choice, but then frozen in. -/
171def ssbMechanism : String :=
172 "System falls into one of equivalent J-cost minima"
173
174/-! ## Nucleation and Metastability -/
175
176/-- For first-order transitions, metastable states exist:
177 - Supercooled liquid