pith. machine review for the scientific record. sign in
class

SymmUnit

definition
show as:
view math explainer →
module
IndisputableMonolith.Cost.JcostCore
domain
Cost
line
162 · github
papers citing
none yet

open explainer

Generate a durable explainer page for this declaration.

open lean source

IndisputableMonolith.Cost.JcostCore on GitHub at line 162.

browse module

All declarations in this module, on Recognition.

explainer page

Tracked in the explainer inventory; generation is lazy so crawlers do not trigger LLM jobs.

open explainer

depends on

used by

formal source

 159    symm; simp [Real.exp_neg t]
 160  simp [Jcost, h]
 161
 162class SymmUnit (F : ℝ → ℝ) : Prop where
 163  symmetric : ∀ {x}, 0 < x → F x = F x⁻¹
 164  unit0 : F 1 = 0
 165
 166class AveragingAgree (F : ℝ → ℝ) : Prop where
 167  agrees : AgreesOnExp F
 168
 169class AveragingDerivation (F : ℝ → ℝ) : Prop extends SymmUnit F where
 170  agrees : AgreesOnExp F
 171
 172class AveragingBounds (F : ℝ → ℝ) : Prop extends SymmUnit F where
 173  upper : ∀ t : ℝ, F (Real.exp t) ≤ Jcost (Real.exp t)
 174  lower : ∀ t : ℝ, Jcost (Real.exp t) ≤ F (Real.exp t)
 175
 176def mkAveragingBounds (F : ℝ → ℝ)
 177  (symm : SymmUnit F)
 178  (upper : ∀ t : ℝ, F (Real.exp t) ≤ Jcost (Real.exp t))
 179  (lower : ∀ t : ℝ, Jcost (Real.exp t) ≤ F (Real.exp t)) :
 180  AveragingBounds F :=
 181{ toSymmUnit := symm, upper := upper, lower := lower }
 182
 183class JensenSketch (F : ℝ → ℝ) : Prop extends SymmUnit F where
 184  axis_upper : ∀ t : ℝ, F (Real.exp t) ≤ Jcost (Real.exp t)
 185  axis_lower : ∀ t : ℝ, Jcost (Real.exp t) ≤ F (Real.exp t)
 186
 187noncomputable def F_ofLog (G : ℝ → ℝ) : ℝ → ℝ := fun x => G (Real.log x)
 188
 189class LogModel (G : ℝ → ℝ) : Prop where
 190  even_log : ∀ t : ℝ, G (-t) = G t
 191  base0 : G 0 = 0
 192  upper_cosh : ∀ t : ℝ, G t ≤ ((Real.exp t + Real.exp (-t)) / 2 - 1)