OAI/Topology/CoarseAssembly/RoeCalculus.lean

GitHub source file

12 declarations, 0 contain sorry, 0 declared as axioms

Finite-propagation matrix calculus

The local-compactness step of the finite-fiber transfer states that sandwiching a locally compact, finite-propagation operator by arbitrary finite-propagation operators preserves local compactness. The multipliers themselves are not assumed locally compact.

  1. theorem OAI.CoarseAssembly.DiscreteRoe.insert_adjoint line 21
  2. theorem OAI.CoarseAssembly.DiscreteRoe.coordinate_adjoint line 27
  3. theorem OAI.CoarseAssembly.DiscreteRoe.entry_star line 30
  4. theorem OAI.CoarseAssembly.DiscreteRoe.vector_eq_sum line 36
  5. theorem OAI.CoarseAssembly.DiscreteRoe.entry_mul_of_finite_column line 50

    Source documentation

    Matrix multiplication is a finite sum whenever the right-hand column has finite support. This avoids any exchange of infinite sums.

    theorem entry_mul_of_finite_column (T S : Operator X H) (x y : X) (s : Finset X)
        (hs : ∀ z, z ∉ s → entry S z y = 0) :
        entry (T * S) x y = ∑ z ∈ s, entry T x z * entry S z y := by
    …

    Mentions: OAI.CoarseAssembly.DiscreteRoe.Operator, OAI.CoarseAssembly.DiscreteRoe.entry

  6. theorem OAI.CoarseAssembly.DiscreteRoe.PropagationLE.star line 66
  7. theorem OAI.CoarseAssembly.DiscreteRoe.column_support line 74
  8. theorem OAI.CoarseAssembly.DiscreteRoe.PropagationLE.mul line 82
  9. theorem OAI.CoarseAssembly.DiscreteRoe.compact_sum line 98
  10. theorem OAI.CoarseAssembly.DiscreteRoe.CompactEntries.mul_left line 105
  11. theorem OAI.CoarseAssembly.DiscreteRoe.CompactEntries.mul_right line 116
  12. theorem OAI.CoarseAssembly.DiscreteRoe.generator_sandwich line 129

    Source documentation

    Finite-propagation multipliers preserve locally compact generators. In particular this applies to amplified finite-propagation projections, without asserting that those projections are locally compact.

    theorem generator_sandwich {A Q : Operator X H} {q : ℝ}
        (hA : Generator A) (hq : 0 ≤ q) (hQ : PropagationLE q Q) :
        Generator (Q * A * Q) := by
    …

    Mentions: OAI.CoarseAssembly.DiscreteRoe.Operator, OAI.CoarseAssembly.DiscreteRoe.Generator, OAI.CoarseAssembly.DiscreteRoe.PropagationLE