def
definition
axionProperties
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IndisputableMonolith.StandardModel.StrongCP on GitHub at line 104.
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101 axion_mass : ℝ -- Typically 10⁻⁶-10⁻³ eV
102 couples_to : List String
103
104def axionProperties : AxionSolution := {
105 pq_scale := 1e10, -- GeV
106 axion_mass := 1e-5, -- eV
107 couples_to := ["photons", "nucleons", "electrons"]
108}
109
110/-- Axions are also a dark matter candidate! -/
111def axionDarkMatter : String :=
112 "If f_a ~ 10¹² GeV, axions can be all of dark matter"
113
114/-! ## RS Solution: 8-Tick Quantization -/
115
116/-- In RS, θ is quantized by 8-tick symmetry:
117
118 The allowed values are: θ = 2πk/8 = πk/4 for k ∈ {0,1,...,7}
119
120 This gives only 8 allowed values:
121 0, π/4, π/2, 3π/4, π, 5π/4, 3π/2, 7π/4 -/
122noncomputable def allowedTheta : List ℝ := [0, π/4, π/2, 3*π/4, π, 5*π/4, 3*π/2, 7*π/4]
123
124/-- J-cost of each θ value:
125
126 θ = 0 and θ = π have lowest J-cost (CP-conserving).
127 Other values have higher J-cost.
128
129 J-cost selection: θ = 0 is preferred. -/
130noncomputable def thetaJCost (θ : ℝ) : ℝ :=
131 (1 - Real.cos θ) -- Minimum at θ = 0
132
133theorem theta_zero_minimizes :
134 ∀ θ, thetaJCost 0 ≤ thetaJCost θ := by