def
definition
w_t_display
show as:
view math explainer →
open explainer
Read the cached plain-language explainer.
open lean source
IndisputableMonolith.Gravity.ILG on GitHub at line 73.
browse module
All declarations in this module, on Recognition.
explainer page
depends on
used by
formal source
70
71@[simp] def w_t (P : Params) (Tdyn τ0 : ℝ) : ℝ := w_t_with defaultConfig P Tdyn τ0
72
73@[simp] def w_t_display (P : Params) (B : BridgeData) (Tdyn : ℝ) : ℝ :=
74 w_t_with defaultConfig P Tdyn B.tau0
75
76lemma eps_t_le_one_default : defaultConfig.eps_t ≤ (1 : ℝ) := by
77 norm_num
78
79/-- Reference identity under nonzero tick: w_t(τ0, τ0) = 1. -/
80lemma w_t_ref_with (cfg : Config) (hcfg : ConfigProps cfg)
81 (P : Params) (τ0 : ℝ) (hτ : τ0 ≠ 0) : w_t_with cfg P τ0 τ0 = 1 := by
82 dsimp [w_t_with]
83 have hdiv : τ0 / τ0 = (1 : ℝ) := by
84 field_simp [hτ]
85 have hmax : max cfg.eps_t (τ0 / τ0) = (1 : ℝ) := by
86 simpa [hdiv, max_eq_right hcfg.eps_t_le_one]
87 simp [hmax]
88
89lemma w_t_ref (P : Params) (τ0 : ℝ) (hτ : τ0 ≠ 0) : w_t P τ0 τ0 = 1 :=
90 w_t_ref_with defaultConfig defaultConfig_props P τ0 hτ
91
92lemma w_t_rescale_with (cfg : Config) (P : Params) (c Tdyn τ0 : ℝ) (hc : 0 < c) :
93 w_t_with cfg P (c * Tdyn) (c * τ0) = w_t_with cfg P Tdyn τ0 := by
94 dsimp [w_t_with]
95 have hc0 : (c : ℝ) ≠ 0 := ne_of_gt hc
96 have : (c * Tdyn) / (c * τ0) = Tdyn / τ0 := by field_simp [hc0]
97 simp [this]
98
99lemma w_t_rescale (P : Params) (c Tdyn τ0 : ℝ) (hc : 0 < c) :
100 w_t P (c * Tdyn) (c * τ0) = w_t P Tdyn τ0 :=
101 w_t_rescale_with defaultConfig P c Tdyn τ0 hc
102
103/-- Nonnegativity of time-kernel under ParamProps. -/