refactor: Higgs potential
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2 changed files with 113 additions and 396 deletions
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@ -251,8 +251,6 @@ lemma pos_𝓵_sol_exists_iff (h𝓵 : 0 < P.𝓵 ) (c : ℝ) : (∃ φ x, P.toF
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-/
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/-- The proposition on the coefficents for a potential to be bounded. -/
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def IsBounded : Prop :=
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∃ c, ∀ Φ x, c ≤ P.toFun Φ x
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@ -317,376 +315,97 @@ lemma isBounded_of_𝓵_pos (h : 0 < P.𝓵) : P.IsBounded := by
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-/
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lemma 𝓵_pos_isMinOn_iff (h : 0 < P.𝓵) :
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IsMinOn (fun (φ, x) => P.toFun φ x) Set.univ (φ, x) ↔
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(P.μ2 < 0 ∧ φ x = 0) ∨ (0 ≤ P.μ2 ∧ ‖φ‖_H ^ 2 x = P.μ2 / (2 * P.𝓵)) := by
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lemma eq_zero_iff_of_μSq_nonpos_𝓵_pos (h𝓵 : 0 < P.𝓵) (hμ2 : P.μ2 ≤ 0) (φ : HiggsField)
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(x : SpaceTime) : P.toFun φ x = 0 ↔ φ x = 0 := by
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rw [P.toFun_eq_zero_iff (ne_of_lt h𝓵).symm]
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simp only [or_iff_left_iff_imp]
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intro h
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have h1 := div_nonpos_of_nonpos_of_nonneg hμ2 (le_of_lt h𝓵)
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rw [← h] at h1
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have hx : 0 ≤ ‖φ‖_H ^ 2 x := by exact normSq_nonneg φ x
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have hx' : ‖φ‖_H ^ 2 x = 0 := by linarith
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simpa using hx'
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lemma isMinOn_iff_of_μSq_nonpos_𝓵_pos (h𝓵 : 0 < P.𝓵) (hμ2 : P.μ2 ≤ 0) (φ : HiggsField)
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(x : SpaceTime) : IsMinOn (fun (φ, x) => P.toFun φ x) Set.univ (φ, x)
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↔ P.toFun φ x = 0 := by
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have h1 := P.pos_𝓵_sol_exists_iff h𝓵
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simp [hμ2] at h1
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rw [isMinOn_univ_iff]
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simp
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by_cases hμ2 : P.μ2 < 0
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· simp [hμ2, not_le_of_lt hμ2]
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refine Iff.intro (fun h1 => ?_) (fun h1 => ?_)
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· have hx := P.pos_𝓵_sol_exists_iff h
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simp [hμ2, not_le_of_lt hμ2] at hx
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have h1' := h1 HiggsField.zero
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sorry
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· sorry
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· sorry
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refine Iff.intro (fun h => ?_) (fun h => ?_)
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· have h1' : P.toFun φ x ≤ 0 := by
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simpa using h HiggsField.zero 0
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have h1'' : 0 ≤ P.toFun φ x := by
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have hx := (h1 (P.toFun φ x)).mp ⟨φ, x, rfl⟩
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rcases hx with hx | hx
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· exact hx.2
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· have hμ2' : P.μ2 = 0 := by
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linarith
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simpa [hμ2'] using hx.2
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linarith
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· rw [h]
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intro φ' x'
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have h1' := (h1 (P.toFun φ' x')).mp ⟨φ', x', rfl⟩
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rcases h1' with h1' | h1'
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· exact h1'.2
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· have hμ2' : P.μ2 = 0 := by
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linarith
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simpa [hμ2'] using h1'.2
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lemma isMinOn_iff_field_of_μSq_nonpos_𝓵_pos (h𝓵 : 0 < P.𝓵) (hμ2 : P.μ2 ≤ 0) (φ : HiggsField)
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(x : SpaceTime) : IsMinOn (fun (φ, x) => P.toFun φ x) Set.univ (φ, x)
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↔ φ x = 0 := by
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rw [P.isMinOn_iff_of_μSq_nonpos_𝓵_pos h𝓵 hμ2 φ x]
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exact P.eq_zero_iff_of_μSq_nonpos_𝓵_pos h𝓵 hμ2 φ x
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lemma isMinOn_iff_of_μSq_nonneg_𝓵_pos (h𝓵 : 0 < P.𝓵) (hμ2 : 0 ≤ P.μ2) (φ : HiggsField)
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(x : SpaceTime) : IsMinOn (fun (φ, x) => P.toFun φ x) Set.univ (φ, x) ↔
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P.toFun φ x = - P.μ2 ^ 2 / (4 * P.𝓵) := by
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have h1 := P.pos_𝓵_sol_exists_iff h𝓵
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simp [hμ2, not_lt.mpr hμ2] at h1
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rw [isMinOn_univ_iff]
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simp
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refine Iff.intro (fun h => ?_) (fun h => ?_)
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· obtain ⟨φ', x', hφ'⟩ := (h1 (- P.μ2 ^ 2 / (4 * P.𝓵))).mpr (by rfl)
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have h' := h φ' x'
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rw [hφ'] at h'
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have hφ := (h1 (P.toFun φ x)).mp ⟨φ, x, rfl⟩
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linarith
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· intro φ' x'
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rw [h]
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exact (h1 (P.toFun φ' x')).mp ⟨φ', x', rfl⟩
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lemma isMinOn_iff_field_of_μSq_nonneg_𝓵_pos (h𝓵 : 0 < P.𝓵) (hμ2 : 0 ≤ P.μ2) (φ : HiggsField)
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(x : SpaceTime) : IsMinOn (fun (φ, x) => P.toFun φ x) Set.univ (φ, x) ↔
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‖φ‖_H ^ 2 x = P.μ2 /(2 * P.𝓵) := by
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rw [P.isMinOn_iff_of_μSq_nonneg_𝓵_pos h𝓵 hμ2 φ x, ← P.quadDiscrim_eq_zero_iff_normSq
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(Ne.symm (ne_of_lt h𝓵)), P.quadDiscrim_eq_zero_iff (Ne.symm (ne_of_lt h𝓵))]
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theorem isMinOn_iff_field_of_𝓵_pos (h𝓵 : 0 < P.𝓵) (φ : HiggsField) (x : SpaceTime) :
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IsMinOn (fun (φ, x) => P.toFun φ x) Set.univ (φ, x) ↔
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(0 ≤ P.μ2 ∧ ‖φ‖_H ^ 2 x = P.μ2 /(2 * P.𝓵)) ∨ (P.μ2 < 0 ∧ φ x = 0) := by
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by_cases hμ2 : 0 ≤ P.μ2
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· simpa [not_lt.mpr hμ2, hμ2] using P.isMinOn_iff_field_of_μSq_nonneg_𝓵_pos h𝓵 hμ2 φ x
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· simpa [hμ2, lt_of_not_ge hμ2] using P.isMinOn_iff_field_of_μSq_nonpos_𝓵_pos h𝓵 (by linarith) φ x
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lemma isMaxOn_iff_isMinOn_neg (φ : HiggsField) (x : SpaceTime) :
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IsMaxOn (fun (φ, x) => P.toFun φ x) Set.univ (φ, x) ↔
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IsMinOn (fun (φ, x) => P.neg.toFun φ x) Set.univ (φ, x) := by
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simp
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rw [isMaxOn_univ_iff, isMinOn_univ_iff]
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simp_all only [Prod.forall, neg_le_neg_iff]
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lemma isMaxOn_iff_field_of_𝓵_neg (h𝓵 : P.𝓵 < 0) (φ : HiggsField) (x : SpaceTime) :
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IsMaxOn (fun (φ, x) => P.toFun φ x) Set.univ (φ, x) ↔
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(P.μ2 ≤ 0 ∧ ‖φ‖_H ^ 2 x = P.μ2 /(2 * P.𝓵)) ∨ (0 < P.μ2 ∧ φ x = 0) := by
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rw [P.isMaxOn_iff_isMinOn_neg,
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P.neg.isMinOn_iff_field_of_𝓵_pos (by simpa using h𝓵)]
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simp
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end Potential
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/-- The Higgs potential of the form `- μ² * |φ|² + 𝓵 * |φ|⁴`. -/
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@[simp]
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def potential (μ2 𝓵 : ℝ) (φ : HiggsField) (x : SpaceTime) : ℝ :=
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- μ2 * ‖φ‖_H ^ 2 x + 𝓵 * ‖φ‖_H ^ 2 x * ‖φ‖_H ^ 2 x
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/-!
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## Smoothness of the potential
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-/
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lemma potential_smooth (μSq lambda : ℝ) (φ : HiggsField) :
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Smooth 𝓘(ℝ, SpaceTime) 𝓘(ℝ, ℝ) (fun x => φ.potential μSq lambda x) := by
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simp only [potential, normSq, neg_mul]
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exact (smooth_const.smul φ.normSq_smooth).neg.add
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((smooth_const.smul φ.normSq_smooth).smul φ.normSq_smooth)
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namespace potential
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/-!
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## Basic properties
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-/
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lemma complete_square (μ2 𝓵 : ℝ) (h : 𝓵 ≠ 0) (φ : HiggsField) (x : SpaceTime) :
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potential μ2 𝓵 φ x = 𝓵 * (‖φ‖_H ^ 2 x - μ2 / (2 * 𝓵)) ^ 2 - μ2 ^ 2 / (4 * 𝓵) := by
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simp only [potential]
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field_simp
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ring
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lemma as_quad (μ2 𝓵 : ℝ) (φ : HiggsField) (x : SpaceTime) :
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𝓵 * ‖φ‖_H ^ 2 x * ‖φ‖_H ^ 2 x + (- μ2) * ‖φ‖_H ^ 2 x + (- potential μ2 𝓵 φ x) = 0 := by
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simp only [normSq, neg_mul, potential, neg_add_rev, neg_neg]
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ring
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/-- The discriminant of the quadratic formed by the potential is non-negative. -/
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lemma discrim_nonneg (μ2 : ℝ) {𝓵 : ℝ} (h : 𝓵 ≠ 0) (φ : HiggsField) (x : SpaceTime) :
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0 ≤ discrim 𝓵 (- μ2) (- potential μ2 𝓵 φ x) := by
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have h1 := as_quad μ2 𝓵 φ x
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rw [quadratic_eq_zero_iff_discrim_eq_sq] at h1
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· simp only [h1, ne_eq, div_eq_zero_iff, OfNat.ofNat_ne_zero, or_false]
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exact sq_nonneg (2 * 𝓵 * ‖φ‖_H ^ 2 x + - μ2)
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· exact h
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lemma discrim_eq_sqrt_discrim_mul_self (μ2 : ℝ) {𝓵 : ℝ} (h : 𝓵 ≠ 0) (φ : HiggsField)
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(x : SpaceTime) :
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discrim 𝓵 (- μ2) (- potential μ2 𝓵 φ x) = Real.sqrt (discrim 𝓵 (- μ2) (- potential μ2 𝓵 φ x)) *
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Real.sqrt (discrim 𝓵 (- μ2) (- potential μ2 𝓵 φ x)) := by
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refine Eq.symm (Real.mul_self_sqrt ?h)
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exact discrim_nonneg μ2 h φ x
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lemma eq_zero_at (μ2 : ℝ) {𝓵 : ℝ} (h : 𝓵 ≠ 0) (φ : HiggsField) (x : SpaceTime)
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(hV : potential μ2 𝓵 φ x = 0) : φ x = 0 ∨ ‖φ‖_H ^ 2 x = μ2 / 𝓵 := by
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have h1 := as_quad μ2 𝓵 φ x
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rw [hV] at h1
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have h2 : ‖φ‖_H ^ 2 x * (𝓵 * ‖φ‖_H ^ 2 x + - μ2) = 0 := by
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linear_combination h1
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simp only [normSq, mul_eq_zero, ne_eq, OfNat.ofNat_ne_zero, not_false_eq_true, pow_eq_zero_iff,
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norm_eq_zero] at h2
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cases' h2 with h2 h2
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· simp_all
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· apply Or.inr
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field_simp at h2 ⊢
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ring_nf
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linear_combination h2
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/-- When `0 < 𝓵`, the potential has a lower bound. -/
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lemma bounded_below (μ2 : ℝ) {𝓵 : ℝ} (h𝓵 : 0 < 𝓵) (φ : HiggsField) (x : SpaceTime) :
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- μ2 ^ 2 / (4 * 𝓵) ≤ potential μ2 𝓵 φ x := by
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have h1 := discrim_nonneg μ2 (ne_of_lt h𝓵).symm φ x
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simp only [discrim, even_two, Even.neg_pow, normSq, neg_mul, neg_add_rev, neg_neg] at h1
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ring_nf at h1
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rw [← neg_le_iff_add_nonneg'] at h1
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rw [show 𝓵 * potential μ2 𝓵 φ x * 4 = (4 * 𝓵) * potential μ2 𝓵 φ x by ring] at h1
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have h2 := (div_le_iff₀' (by simp [h𝓵] : 0 < 4 * 𝓵)).mpr h1
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ring_nf at h2 ⊢
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exact h2
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/-- When `𝓵 < 0`, the potential has an upper bound. -/
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lemma bounded_above (μ2 : ℝ) {𝓵 : ℝ} (h𝓵 : 𝓵 < 0) (φ : HiggsField) (x : SpaceTime) :
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potential μ2 𝓵 φ x ≤ - μ2 ^ 2 / (4 * 𝓵) := by
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have h1 := discrim_nonneg μ2 (ne_of_lt h𝓵) φ x
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simp only [discrim, even_two, Even.neg_pow, normSq, neg_mul, neg_add_rev, neg_neg] at h1
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ring_nf at h1
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rw [← neg_le_iff_add_nonneg'] at h1
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rw [show 𝓵 * potential μ2 𝓵 φ x * 4 = (- 4 * 𝓵) * (- potential μ2 𝓵 φ x) by ring] at h1
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have h2 := le_neg_of_le_neg <| (div_le_iff₀' (by linarith : 0 < - 4 * 𝓵)).mpr h1
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ring_nf at h2 ⊢
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exact h2
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lemma discrim_eq_zero_of_eq_bound (μ2 : ℝ) {𝓵 : ℝ} (h : 𝓵 ≠ 0) (φ : HiggsField) (x : SpaceTime)
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(hV : potential μ2 𝓵 φ x = - μ2 ^ 2 / (4 * 𝓵)) :
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discrim 𝓵 (- μ2) (- potential μ2 𝓵 φ x) = 0 := by
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rw [discrim, hV]
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field_simp
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lemma discrim_ge_zero_of_neg_𝓵 (μ2 : ℝ) {𝓵 : ℝ} (h : 𝓵 < 0) (c : ℝ) :
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0 ≤ discrim 𝓵 (- μ2) (- c) ↔ c ≤ - μ2 ^ 2 / (4 * 𝓵) := by
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rw [discrim]
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simp only [even_two, Even.neg_pow, mul_neg, sub_neg_eq_add]
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rw [← neg_le_iff_add_nonneg', show 4 * 𝓵 * c = (- 4 * 𝓵) * (- c) by ring,
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← (div_le_iff₀' (by linarith : 0 < - 4 * 𝓵)), le_neg]
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ring_nf
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lemma pot_le_zero_of_neg_𝓵 (μ2 : ℝ) {𝓵 : ℝ} (h : 𝓵 < 0) (φ : HiggsField) (x : SpaceTime) :
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(0 < μ2 ∧ potential μ2 𝓵 φ x ≤ 0) ∨ μ2 ≤ 0 := by
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by_cases hμ2 : μ2 ≤ 0
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· simp [hμ2]
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simp only [potential, normSq, neg_mul, neg_add_le_iff_le_add, add_zero, hμ2, or_false]
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apply And.intro (lt_of_not_ge hμ2)
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have h1 : 0 ≤ μ2 * ‖φ x‖ ^ 2 := by
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refine Left.mul_nonneg ?ha ?hb
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· exact le_of_not_ge hμ2
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· exact sq_nonneg ‖φ x‖
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refine le_trans ?_ h1
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exact mul_nonpos_of_nonpos_of_nonneg (mul_nonpos_of_nonpos_of_nonneg (le_of_lt h)
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(sq_nonneg ‖φ x‖)) (sq_nonneg ‖φ x‖)
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lemma exist_sol_iff_of_neg_𝓵 (μ2 : ℝ) {𝓵 : ℝ} (h𝓵 : 𝓵 < 0) (c : ℝ) :
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(∃ φ x, potential μ2 𝓵 φ x = c) ↔ (0 < μ2 ∧ c ≤ 0) ∨
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(μ2 ≤ 0 ∧ c ≤ - μ2 ^ 2 / (4 * 𝓵)) := by
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refine Iff.intro (fun ⟨φ, x, hV⟩ => ?_) (fun h => ?_)
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· rcases pot_le_zero_of_neg_𝓵 μ2 h𝓵 φ x with hr | hr
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· rw [← hV]
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exact Or.inl hr
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· rw [← hV]
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exact Or.inr (And.intro hr (bounded_above μ2 h𝓵 φ x))
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· simp only [potential, neg_mul]
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simp only [← sub_eq_zero, sub_zero]
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ring_nf
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let a := (μ2 - Real.sqrt (discrim 𝓵 (- μ2) (- c))) / (2 * 𝓵)
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have ha : 0 ≤ a := by
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simp only [discrim, even_two, Even.neg_pow, mul_neg, sub_neg_eq_add, a]
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rw [div_nonneg_iff]
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refine Or.inr (And.intro ?_ ?_)
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· rw [sub_nonpos]
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by_cases hμ : μ2 < 0
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· have h1 : 0 ≤ √(μ2 ^ 2 + 4 * 𝓵 * c) := Real.sqrt_nonneg (μ2 ^ 2 + 4 * 𝓵 * c)
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linarith
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· refine Real.le_sqrt_of_sq_le ?_
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rw [le_add_iff_nonneg_right]
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refine mul_nonneg_of_nonpos_of_nonpos ?_ ?_
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· refine mul_nonpos_of_nonneg_of_nonpos ?_ ?_
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· linarith
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· linarith
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· rcases h with h | h
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· linarith
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· have h1 : μ2 = 0 := by linarith
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rw [h1] at h
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simpa using h.2
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· linarith
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use (ofReal a)
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use 0
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rw [ofReal_normSq ha]
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trans 𝓵 * a * a + (- μ2) * a + (- c)
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· ring
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have hd : 0 ≤ (discrim 𝓵 (-μ2) (-c)) := by
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simp only [discrim, even_two, Even.neg_pow, mul_neg, sub_neg_eq_add]
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rcases h with h | h
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· refine Left.add_nonneg (sq_nonneg μ2) ?_
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refine mul_nonneg_of_nonpos_of_nonpos ?_ h.2
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linarith
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· rw [← @neg_le_iff_add_nonneg']
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rw [← le_div_iff_of_neg']
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· exact h.2
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· linarith
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have hdd : discrim 𝓵 (-μ2) (-c) = Real.sqrt (discrim 𝓵 (-μ2) (-c))
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* Real.sqrt (discrim 𝓵 (-μ2) (-c)) := by
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exact (Real.mul_self_sqrt hd).symm
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refine (quadratic_eq_zero_iff (ne_of_gt h𝓵).symm hdd _).mpr ?_
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simp only [neg_neg, or_true, a]
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/-!
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## Boundness of the potential
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-/
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/-- The proposition on the coefficents for a potential to be bounded. -/
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def IsBounded (μ2 𝓵 : ℝ) : Prop :=
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∃ c, ∀ Φ x, c ≤ potential μ2 𝓵 Φ x
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lemma isBounded_𝓵_nonneg {μ2 𝓵 : ℝ} (h : IsBounded μ2 𝓵) :
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0 ≤ 𝓵 := by
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by_contra hl
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rw [not_le] at hl
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obtain ⟨c, hc⟩ := h
|
||||
by_cases hμ : μ2 ≤ 0
|
||||
· by_cases hcz : c ≤ -μ2 ^ 2 / (4 * 𝓵)
|
||||
· have hcm1 : ∃ φ x, potential μ2 𝓵 φ x = c - 1 := by
|
||||
rw [propext (exist_sol_iff_of_neg_𝓵 μ2 hl (c - 1))]
|
||||
apply Or.inr
|
||||
simp_all
|
||||
linarith
|
||||
obtain ⟨φ, x, hφ⟩ := hcm1
|
||||
have hc2 := hc φ x
|
||||
rw [hφ] at hc2
|
||||
linarith
|
||||
· rw [not_le] at hcz
|
||||
have hcm1 : ∃ φ x, potential μ2 𝓵 φ x = -μ2 ^ 2 / (4 * 𝓵) - 1 := by
|
||||
rw [propext (exist_sol_iff_of_neg_𝓵 μ2 hl _)]
|
||||
apply Or.inr
|
||||
simp_all
|
||||
obtain ⟨φ, x, hφ⟩ := hcm1
|
||||
have hc2 := hc φ x
|
||||
rw [hφ] at hc2
|
||||
linarith
|
||||
· rw [not_le] at hμ
|
||||
by_cases hcz : c ≤ 0
|
||||
· have hcm1 : ∃ φ x, potential μ2 𝓵 φ x = c - 1 := by
|
||||
rw [propext (exist_sol_iff_of_neg_𝓵 μ2 hl (c - 1))]
|
||||
apply Or.inl
|
||||
simp_all
|
||||
linarith
|
||||
obtain ⟨φ, x, hφ⟩ := hcm1
|
||||
have hc2 := hc φ x
|
||||
rw [hφ] at hc2
|
||||
linarith
|
||||
· have hcm1 : ∃ φ x, potential μ2 𝓵 φ x = 0 := by
|
||||
rw [propext (exist_sol_iff_of_neg_𝓵 μ2 hl 0)]
|
||||
apply Or.inl
|
||||
simp_all
|
||||
obtain ⟨φ, x, hφ⟩ := hcm1
|
||||
have hc2 := hc φ x
|
||||
rw [hφ] at hc2
|
||||
linarith
|
||||
|
||||
section lowerBound
|
||||
/-!
|
||||
|
||||
## Lower bound on potential
|
||||
|
||||
-/
|
||||
|
||||
variable (μ2 : ℝ) {𝓵 : ℝ} (h𝓵 : 0 < 𝓵)
|
||||
|
||||
include h𝓵
|
||||
/-- The second term of the potential is non-negative. -/
|
||||
lemma snd_term_nonneg (φ : HiggsField) (x : SpaceTime) :
|
||||
0 ≤ 𝓵 * ‖φ‖_H ^ 2 x * ‖φ‖_H ^ 2 x := by
|
||||
rw [mul_nonneg_iff]
|
||||
apply Or.inl
|
||||
simp_all only [normSq, gt_iff_lt, mul_nonneg_iff_of_pos_left, ge_iff_le, norm_nonneg, pow_nonneg,
|
||||
and_self]
|
||||
|
||||
lemma eq_zero_at_of_μSq_nonpos {μ2 : ℝ} (hμ2 : μ2 ≤ 0)
|
||||
(φ : HiggsField) (x : SpaceTime) (hV : potential μ2 𝓵 φ x = 0) : φ x = 0 := by
|
||||
cases' (eq_zero_at μ2 (ne_of_lt h𝓵).symm φ x hV) with h1 h1
|
||||
· exact h1
|
||||
· by_cases hμSqZ : μ2 = 0
|
||||
· simpa [hμSqZ] using h1
|
||||
· refine ((?_ : ¬ 0 ≤ μ2 / 𝓵) (?_)).elim
|
||||
· simp_all [div_nonneg_iff]
|
||||
intro h
|
||||
exact lt_imp_lt_of_le_imp_le (fun _ => h) (lt_of_le_of_ne hμ2 hμSqZ)
|
||||
· rw [← h1]
|
||||
exact normSq_nonneg φ x
|
||||
|
||||
lemma bounded_below_of_μSq_nonpos {μ2 : ℝ}
|
||||
(hμSq : μ2 ≤ 0) (φ : HiggsField) (x : SpaceTime) : 0 ≤ potential μ2 𝓵 φ x := by
|
||||
refine add_nonneg ?_ (snd_term_nonneg h𝓵 φ x)
|
||||
field_simp [mul_nonpos_iff]
|
||||
simp_all [ge_iff_le, norm_nonneg, pow_nonneg, and_self, or_true]
|
||||
|
||||
end lowerBound
|
||||
|
||||
section MinimumOfPotential
|
||||
variable {𝓵 : ℝ}
|
||||
variable (μ2 : ℝ)
|
||||
variable (h𝓵 : 0 < 𝓵)
|
||||
|
||||
/-!
|
||||
|
||||
## Minima of potential
|
||||
|
||||
-/
|
||||
|
||||
include h𝓵
|
||||
lemma normSq_of_eq_bound (φ : HiggsField) (x : SpaceTime)
|
||||
(hV : potential μ2 𝓵 φ x = - μ2 ^ 2 / (4 * 𝓵)) :
|
||||
‖φ‖_H ^ 2 x = μ2 / (2 * 𝓵) := by
|
||||
have h1 := as_quad μ2 𝓵 φ x
|
||||
rw [quadratic_eq_zero_iff_of_discrim_eq_zero _
|
||||
(discrim_eq_zero_of_eq_bound μ2 (ne_of_lt h𝓵).symm φ x hV)] at h1
|
||||
· simp_rw [h1, neg_neg]
|
||||
· exact ne_of_gt h𝓵
|
||||
|
||||
lemma eq_bound_iff (φ : HiggsField) (x : SpaceTime) :
|
||||
potential μ2 𝓵 φ x = - μ2 ^ 2 / (4 * 𝓵) ↔ ‖φ‖_H ^ 2 x = μ2 / (2 * 𝓵) :=
|
||||
Iff.intro (normSq_of_eq_bound μ2 h𝓵 φ x)
|
||||
(fun h ↦ by
|
||||
rw [potential, h]
|
||||
field_simp
|
||||
ring_nf)
|
||||
|
||||
lemma eq_bound_iff_of_μSq_nonpos {μ2 : ℝ}
|
||||
(hμ2 : μ2 ≤ 0) (φ : HiggsField) (x : SpaceTime) :
|
||||
potential μ2 𝓵 φ x = 0 ↔ φ x = 0 :=
|
||||
Iff.intro (fun h ↦ eq_zero_at_of_μSq_nonpos h𝓵 hμ2 φ x h)
|
||||
(fun h ↦ by simp [potential, h])
|
||||
|
||||
lemma eq_bound_IsMinOn (φ : HiggsField) (x : SpaceTime)
|
||||
(hv : potential μ2 𝓵 φ x = - μ2 ^ 2 / (4 * 𝓵)) :
|
||||
IsMinOn (fun (φ, x) => potential μ2 𝓵 φ x) Set.univ (φ, x) := by
|
||||
rw [isMinOn_univ_iff]
|
||||
simp only [normSq, neg_mul, le_neg_add_iff_add_le, ge_iff_le, hv]
|
||||
exact fun (φ', x') ↦ bounded_below μ2 h𝓵 φ' x'
|
||||
|
||||
lemma eq_bound_IsMinOn_of_μSq_nonpos {μ2 : ℝ}
|
||||
(hμ2 : μ2 ≤ 0) (φ : HiggsField) (x : SpaceTime) (hv : potential μ2 𝓵 φ x = 0) :
|
||||
IsMinOn (fun (φ, x) => potential μ2 𝓵 φ x) Set.univ (φ, x) := by
|
||||
rw [isMinOn_univ_iff]
|
||||
simp only [normSq, neg_mul, le_neg_add_iff_add_le, ge_iff_le, hv]
|
||||
exact fun (φ', x') ↦ bounded_below_of_μSq_nonpos h𝓵 hμ2 φ' x'
|
||||
|
||||
lemma bound_reached_of_μSq_nonneg {μ2 : ℝ} (hμ2 : 0 ≤ μ2) :
|
||||
∃ (φ : HiggsField) (x : SpaceTime),
|
||||
potential μ2 𝓵 φ x = - μ2 ^ 2 / (4 * 𝓵) := by
|
||||
use HiggsVec.toField ![√(μ2/(2 * 𝓵)), 0], 0
|
||||
refine (eq_bound_iff μ2 h𝓵 (HiggsVec.toField ![√(μ2/(2 * 𝓵)), 0]) 0).mpr ?_
|
||||
simp only [normSq, HiggsVec.toField, ContMDiffSection.coeFn_mk, PiLp.norm_sq_eq_of_L2,
|
||||
Nat.succ_eq_add_one, Nat.reduceAdd, norm_eq_abs, Fin.sum_univ_two, Fin.isValue, cons_val_zero,
|
||||
abs_ofReal, _root_.sq_abs, cons_val_one, head_cons, map_zero, ne_eq, OfNat.ofNat_ne_zero,
|
||||
not_false_eq_true, zero_pow, add_zero]
|
||||
field_simp [mul_pow]
|
||||
|
||||
lemma IsMinOn_iff_of_μSq_nonneg {μ2 : ℝ} (hμ2 : 0 ≤ μ2) :
|
||||
IsMinOn (fun (φ, x) => potential μ2 𝓵 φ x) Set.univ (φ, x) ↔
|
||||
‖φ‖_H ^ 2 x = μ2 /(2 * 𝓵) := by
|
||||
apply Iff.intro <;> rw [← eq_bound_iff μ2 h𝓵 φ]
|
||||
· intro h
|
||||
obtain ⟨φm, xm, hφ⟩ := bound_reached_of_μSq_nonneg h𝓵 hμ2
|
||||
have hm := isMinOn_univ_iff.mp h (φm, xm)
|
||||
simp only at hm
|
||||
rw [hφ] at hm
|
||||
exact (Real.partialOrder.le_antisymm _ _ (bounded_below μ2 h𝓵 φ x) hm).symm
|
||||
· exact eq_bound_IsMinOn μ2 h𝓵 φ x
|
||||
|
||||
lemma IsMinOn_iff_of_μSq_nonpos {μ2 : ℝ} (hμ2 : μ2 ≤ 0) :
|
||||
IsMinOn (fun (φ, x) => potential μ2 𝓵 φ x) Set.univ (φ, x) ↔ φ x = 0 := by
|
||||
apply Iff.intro <;> rw [← eq_bound_iff_of_μSq_nonpos h𝓵 hμ2 φ]
|
||||
· intro h
|
||||
have h0 := isMinOn_univ_iff.mp h 0
|
||||
have h1 := bounded_below_of_μSq_nonpos h𝓵 hμ2 φ x
|
||||
simp only at h0
|
||||
rw [(eq_bound_iff_of_μSq_nonpos h𝓵 hμ2 0 0).mpr (by rfl)] at h0
|
||||
exact (Real.partialOrder.le_antisymm _ _ h1 h0).symm
|
||||
· exact eq_bound_IsMinOn_of_μSq_nonpos h𝓵 hμ2 φ x
|
||||
|
||||
end MinimumOfPotential
|
||||
|
||||
end potential
|
||||
|
||||
end HiggsField
|
||||
|
||||
end StandardModel
|
||||
|
|
Loading…
Add table
Add a link
Reference in a new issue