Documentation

TauCeti.Analysis.Normed.Operator.RingOpNorm.OpenMapping

Quantitative mapping theorems over Tate rings #

TauCeti.HasZeroSequenceOfUnits.isOpenMap proves Henkel's topological open mapping theorem for surjective equivariant additive maps out of a complete first-countable non-archimedean group into a Baire target over any scalar ring admitting a zero sequence of units. When the scalar ring is a Tate normed ring (TauCeti.NormedRing.IsTate), the powers of a multiplicative pseudo-uniformiser supply that zero sequence of units, and exact scaling by integer powers of the pseudo-uniformiser turns topological openness into quantitative linear preimage bounds.

This file develops those quantitative mapping theorems and their finite-free consequences over any Tate seminormed ring R (no commutativity or ultrametric hypothesis on R is needed unless R^n itself serves as the ultrametric domain):

The API and the bounded-inverse, range-equivalence, bijective-map, unit and closed-graph packaging are adapted from Mathlib/Analysis/Normed/Operator/Banach.lean, in particular LinearEquiv.continuous_symm, LinearEquiv.toContinuousLinearEquivOfContinuous, ContinuousLinearMap.equivRange, ContinuousLinearMap.isClosed_range_iff_antilipschitz_of_injective, ContinuousLinearEquiv.ofBijective, ContinuousLinearMap.isUnit_iff_bijective, ContinuousLinearMap.ofIsClosedGraph and ContinuousLinearMap.ofSeqClosedGraph.

References #

theorem TauCeti.NormedRing.PseudoUniformizer.exists_preimage_norm_le_of_ball_subset {R : Type u_1} {M : Type u_2} {N : Type u_3} [SeminormedRing R] [SeminormedAddCommGroup M] [Module R M] [IsBoundedSMul R M] [NormedAddCommGroup N] [Module R N] [IsBoundedSMul R N] (ϖ : PseudoUniformizer R) (f : M →ₗ[R] N) {δ R₀ : ℝ} (k : ℤ) (hδ : ‖↑ϖ.unit‖ ^ k < δ) (hball : Metric.ball 0 δ ⊆ ⇑f '' Metric.ball 0 R₀) (y : N) :
∃ (x : M), f x = y ∧ ‖x‖ ≤ R₀ * (‖↑ϖ.unit‖ ^ (k + 1))⁻¹ * ‖y‖

Quantitative preimage bound from ball containment. If ϖ is a multiplicative pseudo-uniformiser on R, ‖(ϖ.unit : R)‖ ^ k < δ, and ball (0 : N) δ ⊆ f '' ball (0 : M) R₀, then every y : N admits x : M with f x = y and ‖x‖ ≤ R₀ * (‖(ϖ.unit : R)‖ ^ (k + 1))⁻¹ * ‖y‖.

theorem LinearMap.exists_preimage_norm_le_of_nhds_zero {R : Type u_1} {M : Type u_2} {N : Type u_3} [SeminormedRing R] [TauCeti.NormedRing.IsTate R] [SeminormedAddCommGroup M] [Module R M] [IsBoundedSMul R M] [NormedAddCommGroup N] [Module R N] [IsBoundedSMul R N] (f : M →ₗ[R] N) (hnhds : ⇑f '' Metric.ball 0 1 ∈ nhds 0) :
∃ C > 0, ∀ (y : N), ∃ (x : M), f x = y ∧ ‖x‖ ≤ C * ‖y‖

If the image of the unit ball under f : M →ₗ[R] N is a neighbourhood of 0 in a normed module N over a Tate ring R, then f is surjective and admits a constant C > 0 such that every y : N lifts to x : M with ‖x‖ ≤ C * ‖y‖.

theorem LinearMap.exists_preimage_norm_le_of_isOpenMap {R : Type u_1} {M : Type u_2} {N : Type u_3} [SeminormedRing R] [TauCeti.NormedRing.IsTate R] [SeminormedAddCommGroup M] [Module R M] [IsBoundedSMul R M] [NormedAddCommGroup N] [Module R N] [IsBoundedSMul R N] (f : M →ₗ[R] N) (hopen : IsOpenMap ⇑f) :
∃ C > 0, ∀ (y : N), ∃ (x : M), f x = y ∧ ‖x‖ ≤ C * ‖y‖

Any open linear map into a normed module over a Tate ring is surjective and admits a linear preimage bound ‖x‖ ≤ C * ‖y‖ with C > 0.

Open Mapping Theorem for normed modules over a Tate ring. A surjective continuous linear map from a complete ultrametric seminormed module to a complete normed module over a Tate ring is an open map.

theorem LinearMap.exists_preimage_norm_le_of_surjective {R : Type u_1} {M : Type u_2} {N : Type u_3} [SeminormedRing R] [TauCeti.NormedRing.IsTate R] [SeminormedAddCommGroup M] [IsUltrametricDist M] [CompleteSpace M] [Module R M] [IsBoundedSMul R M] [NormedAddCommGroup N] [CompleteSpace N] [Module R N] [IsBoundedSMul R N] (f : M →ₗ[R] N) (hf : Continuous ⇑f) (hsurj : Function.Surjective ⇑f) :
∃ C > 0, ∀ (y : N), ∃ (x : M), f x = y ∧ ‖x‖ ≤ C * ‖y‖

Quantitative Open Mapping Theorem for linear maps over a Tate ring: every surjective continuous linear map from a complete ultrametric seminormed module to a complete normed module admits a constant C > 0 such that every y : N lifts to x : M with ‖x‖ ≤ C * ‖y‖.

Bounded Inverse Theorem for linear equivalences over a Tate ring: the inverse of a continuous linear equivalence from a complete ultrametric seminormed module to a complete normed module is continuous.

Promote a continuous linear equivalence e : M ≃ₗ[R] N from a complete ultrametric seminormed module to a complete normed module over a Tate ring to a bundled ContinuousLinearEquiv.

Instances For

    Bounded Inverse Theorem: a bijective continuous linear map from a complete ultrametric seminormed module to a complete normed module over a Tate ring is a continuous linear equivalence.

    Instances For

      A surjective continuous linear map from a complete ultrametric seminormed module to a complete normed module over a Tate ring is an open map.

      A surjective continuous linear map from a complete ultrametric seminormed module to a complete normed module over a Tate ring is a quotient map.

      theorem ContinuousLinearMap.exists_preimage_norm_le_of_isTate {R : Type u_1} {M : Type u_2} {N : Type u_3} [SeminormedRing R] [TauCeti.NormedRing.IsTate R] [SeminormedAddCommGroup M] [IsUltrametricDist M] [CompleteSpace M] [Module R M] [IsBoundedSMul R M] [NormedAddCommGroup N] [CompleteSpace N] [Module R N] [IsBoundedSMul R N] (f : M →L[R] N) (hsurj : Function.Surjective ⇑f) :
      ∃ C > 0, ∀ (y : N), ∃ (x : M), f x = y ∧ ‖x‖ ≤ C * ‖y‖

      Quantitative Open Mapping Theorem: for a surjective continuous linear map f : M →L[R] N from a complete ultrametric seminormed module to a complete normed module over a Tate ring, there exists C > 0 such that every y : N lifts to x : M with ‖x‖ ≤ C * ‖y‖.

      A continuous linear map f : M →L[R] N with closed range from a complete ultrametric seminormed module to a complete normed module over a Tate ring is a strict morphism (Topology.IsStrictMap).

      A continuous linear map f : M →L[R] N with closed range from a complete ultrametric seminormed module to a complete normed module over a Tate ring is open onto its range.

      Quantitative preimage bound for closed-range operators: if f : M →L[R] N from a complete ultrametric seminormed module to a complete normed module over a Tate ring has closed range, there exists C > 0 such that every y ∈ Set.range f lifts to x : M with f x = y and ‖x‖ ≤ C * ‖y‖.

      If f : M →L[R] N from a complete ultrametric seminormed module to a complete normed module over a Tate ring is injective and has closed range, then ‖x‖ ≤ C * ‖f x‖ for some C > 0.

      If f : M →L[R] N from a complete ultrametric seminormed module to a complete normed module over a Tate ring is injective and has closed range, then f is AntilipschitzWith K for some K ≠ 0.

      For an injective continuous linear map f : M' →L[R] N from a complete ultrametric normed module to a complete normed module over a Tate ring, the range of f is closed if and only if f is antilipschitz.

      noncomputable def ContinuousLinearMap.equivRangeOfIsTate {R : Type u_1} {M : Type u_2} {N : Type u_3} [SeminormedRing R] [TauCeti.NormedRing.IsTate R] [SeminormedAddCommGroup M] [IsUltrametricDist M] [CompleteSpace M] [Module R M] [IsBoundedSMul R M] [NormedAddCommGroup N] [CompleteSpace N] [Module R N] [IsBoundedSMul R N] (f : M →L[R] N) (hinj : Function.Injective ⇑f) (hclosed : IsClosed (Set.range ⇑f)) :
      M ≃L[R] ↥(↑f).range

      An injective continuous linear map with closed range from a complete ultrametric seminormed module to a complete normed module over a Tate ring induces a continuous linear equivalence onto its range.

      Instances For

        A continuous linear endomorphism of a complete ultrametric normed module over a Tate ring is a unit in N →L[R] N if and only if it is bijective.

        Closed graph theorem #

        Closed Graph Theorem for normed modules over a Tate ring: a linear map from a complete ultrametric normed module to a complete ultrametric seminormed module whose graph is closed is continuous.

        Sequential Closed Graph Theorem for normed modules over a Tate ring: a linear map from a complete ultrametric normed module to a complete ultrametric seminormed module whose graph is sequentially closed is continuous.

        Construct a bundled continuous linear map from a linear map with closed graph over a Tate ring.

        Instances For

          Construct a bundled continuous linear map from a linear map with sequentially closed graph over a Tate ring.

          Instances For
            @[simp]

            Quantitative finite spanning #

            theorem TauCeti.exists_linearCombination_eq_and_norm_le {R : Type u_1} {N : Type u_2} {ι : Type u_3} [Fintype ι] [SeminormedRing R] [IsUltrametricDist R] [CompleteSpace R] [NormedRing.IsTate R] [NormedAddCommGroup N] [CompleteSpace N] [Module R N] [IsBoundedSMul R N] (v : ι → N) (hspan : Submodule.span R (Set.range v) = ⊤) :
            ∃ C > 0, ∀ (y : N), ∃ (c : ι → R), ∑ i : ι, c i • v i = y ∧ ‖c‖ ≤ C * ‖y‖

            Quantitative finite spanning over a complete ultrametric Tate ring. If a finite family v : ι → N spans a complete normed module N over a complete ultrametric Tate ring R, then there exists C > 0 such that every y : N can be written as ∑ i, c i • v i with ‖c‖ ≤ C * ‖y‖ (and hence ‖c i‖ ≤ C * ‖y‖ for every i).