OAI/Analysis/Nonexpansive/TailMaps.lean
22 declarations, 0 contain sorry, 0 declared as axioms
Resolvent tail families
The outer resolvent in every tail map gives a uniform approximate fixed point bound. Convex hulls are taken in the ambient vector space of maps. Precomposition is linear on that vector space; only this linear operation is distributed over convex combinations.
- def
OAI.ReflexiveFixedPoints.tailFamilyline 28Source documentation
Tail maps retain their actual outer resolvent and generated inner map.
def tailFamily (m : ℕ) : Set (K → K) := …
- theorem
OAI.ReflexiveFixedPoints.tailFamily_nonemptyline 33 - theorem
OAI.ReflexiveFixedPoints.tailFamily_generatedline 38 - theorem
OAI.ReflexiveFixedPoints.tailFamily_antitoneline 44 - theorem
OAI.ReflexiveFixedPoints.tailFamily_nonexpansiveline 49 - theorem
OAI.ReflexiveFixedPoints.tailFamily_defect_leline 55 - theorem
OAI.ReflexiveFixedPoints.tailFamily_precompline 68Source documentation
Appending any generated map on the input side retains the same tail.
theorem tailFamily_precomp {m : ℕ} {h g : K → K} (hh : h ∈ tailFamily hKclosed hKconvex T hT m) (hg : Generated hKclosed hKconvex T hT g) : h ∘ g ∈ tailFamily hKclosed hKconvex T hT m := by …Mentions: OAI.ReflexiveFixedPoints.tailFamily, OAI.ReflexiveFixedPoints.Generated
- def
OAI.ReflexiveFixedPoints.ambientTailFamilyline 76Source documentation
Tail maps represented in the actual vector space of ambient-valued maps.
def ambientTailFamily (m : ℕ) : Set (K → X) := …
- def
OAI.ReflexiveFixedPoints.ambientTailConvexHullline 80Source documentation
The algebraic convex hull, before pointwise weak closure is taken.
def ambientTailConvexHull (m : ℕ) : Set (K → X) := …
- theorem
OAI.ReflexiveFixedPoints.ambientTailFamily_nonemptyline 83 - theorem
OAI.ReflexiveFixedPoints.ambientTailFamily_antitoneline 87 - theorem
OAI.ReflexiveFixedPoints.ambientTailConvexHull_nonemptyline 92 - theorem
OAI.ReflexiveFixedPoints.ambientTailConvexHull_antitoneline 96 - theorem
OAI.ReflexiveFixedPoints.convex_ambientTailConvexHullline 101 - theorem
OAI.ReflexiveFixedPoints.ambientTailFamily_subset_generatedline 105 - theorem
OAI.ReflexiveFixedPoints.ambientTailConvexHull_subset_generatedline 111 - theorem
OAI.ReflexiveFixedPoints.ambientTailConvexHull_representativeline 118Source documentation
Every element of the ambient convex hull is a genuine generated selfmap.
theorem ambientTailConvexHull_representative {m : ℕ} {f : K → X} (hf : f ∈ ambientTailConvexHull hKclosed hKconvex T hT m) : ∃ g : K → K, Generated hKclosed hKconvex T hT g ∧ ambientMap g = f := …Mentions: OAI.ReflexiveFixedPoints.ambientTailConvexHull, OAI.ReflexiveFixedPoints.Generated, OAI.ReflexiveFixedPoints.ambientMap
- theorem
OAI.ReflexiveFixedPoints.ambientTailConvexHull_mapsToline 123 - theorem
OAI.ReflexiveFixedPoints.ambientTailConvexHull_nonexpansiveline 130 - def
OAI.ReflexiveFixedPoints.precompLinearline 140Source documentation
Precomposition by a fixed selfmap is a linear map on ambient-valued maps.
def precompLinear (g : K → K) : (K → X) →ₗ[ℝ] (K → X) where …
- theorem
OAI.ReflexiveFixedPoints.ambientTailConvexHull_precompline 145 - theorem
OAI.ReflexiveFixedPoints.ambientTailConvexHull_compline 160Source documentation
Composition closure follows from linear precomposition, without a continuity or affinity assumption on the nonlinear maps.
theorem ambientTailConvexHull_comp {m : ℕ} {f g : K → K} (hf : ambientMap f ∈ ambientTailConvexHull hKclosed hKconvex T hT m) (hg : ambientMap g ∈ ambientTailConvexHull hKclosed hKconvex T hT m) : ambientMap (f ∘ g) ∈ ambientTailConvexHull hKclosed hKconvex T hT m := by …Mentions: OAI.ReflexiveFixedPoints.ambientMap, OAI.ReflexiveFixedPoints.ambientTailConvexHull