OAI/GroupTheory/PolycyclicRecognition/Geometry/ExponentialEmbedding.lean

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3 declarations, 0 contain sorry, 0 declared as axioms

Closed embeddings from compatible global exponential charts

An injective map of finite-dimensional real Lie algebras is closed in linear coordinates. Compatible global exponential charts transfer that property to the integrated subgroup map. This supplies the properness required for fixed-slice packing, without adding a closed-subgroup hypothesis.

  1. theorem OAI.PolycyclicRecognition.isClosedEmbedding_of_compatible_charts line 27

    Source documentation

    Global exponential charts turn an injective linear inclusion into a closed topological embedding. No group-theoretic splitting is required.

    theorem isClosedEmbedding_of_compatible_charts
        (cN : V ≃ₜ N) (cG : U ≃ₜ G) (j : V →ₗ[ℝ] U)
        (hj : Function.Injective j) (f : N → G)
        (hf : ∀ x, f (cN x) = cG (j x)) : Topology.IsClosedEmbedding f := by
    …
  2. theorem OAI.PolycyclicRecognition.isClosedEmbedding_of_exponential_compatibility line 40

    Source documentation

    The same conclusion with separately named intrinsic exponentials.

    theorem isClosedEmbedding_of_exponential_compatibility
        (cN : V ≃ₜ N) (cG : U ≃ₜ G) (ExpN : V → N) (ExpG : U → G)
        (hN : ∀ x, cN x = ExpN x) (hG : ∀ x, cG x = ExpG x)
        (j : V →ₗ[ℝ] U) (hj : Function.Injective j) (f : N → G)
        (hf : ∀ x, f (ExpN x) = ExpG (j x)) : Topology.IsClosedEmbedding f := by
    …
  3. theorem OAI.PolycyclicRecognition.isCompact_preimage_of_exponential_compatibility line 52

    Source documentation

    In particular compact ambient regions have compact sets of subgroup parameters. This will bound fixed-radius ball multiplicities.

    theorem isCompact_preimage_of_exponential_compatibility
        (cN : V ≃ₜ N) (cG : U ≃ₜ G) (ExpN : V → N) (ExpG : U → G)
        (hN : ∀ x, cN x = ExpN x) (hG : ∀ x, cG x = ExpG x)
        (j : V →ₗ[ℝ] U) (hj : Function.Injective j) (f : N → G)
        (hf : ∀ x, f (ExpN x) = ExpG (j x))
        {K : Set G} (hK : IsCompact K) : IsCompact (f ⁻¹' K) :=
    …