OAI/Analysis/Kaplansky/Shift.lean

GitHub source file

17 declarations, 0 contain sorry, 0 declared as axioms

Hilbert shifts, their relations, and block operator bounds.

  1. abbrev OAI.Kaplansky.FiberHilbertSum line 18
  2. def OAI.Kaplansky.levelInclusion line 20
  3. theorem OAI.Kaplansky.successor_orthogonal line 24
  4. def OAI.Kaplansky.successorInclusion line 34

    Source documentation

    Isometric insertion of a zero level at the start of the sum.

    def successorInclusion : lp (fun j => E (j+1)) 2 →ₗᵢ[ℂ] FiberHilbertSum E :=
    …

    Mentions: OAI.Kaplansky.FiberHilbertSum

  5. def OAI.Kaplansky.forwardShift line 37
  6. theorem OAI.Kaplansky.forwardShift_norm_le line 41
  7. theorem OAI.Kaplansky.forwardShift_single line 49
  8. theorem OAI.Kaplansky.forwardShift_apply_zero line 73

    Source documentation

    A forward shift has zero output in degree zero.

    theorem forwardShift_apply_zero (T : ∀ j, E j →L[ℂ] E (j+1)) (hT : ∀ j, ‖T j‖ ≤ 1)
        (f : FiberHilbertSum E) : forwardShift T hT f 0 = 0 := by
    …

    Mentions: OAI.Kaplansky.FiberHilbertSum, OAI.Kaplansky.forwardShift

  9. theorem OAI.Kaplansky.forwardShift_apply_succ line 85

    Source documentation

    On degree j+1, the forward shift is exactly its j-th block.

    theorem forwardShift_apply_succ (T : ∀ j, E j →L[ℂ] E (j+1)) (hT : ∀ j, ‖T j‖ ≤ 1)
        (f : FiberHilbertSum E) (j : ℕ) : forwardShift T hT f (j+1) = T j (f j) := by
    …

    Mentions: OAI.Kaplansky.FiberHilbertSum, OAI.Kaplansky.forwardShift

  10. theorem OAI.Kaplansky.forwardShift_adjoint_apply line 100

    Source documentation

    The adjoint lowers degree, using the adjoint of the actual block.

    theorem forwardShift_adjoint_apply (T : ∀ j, E j →L[ℂ] E (j+1)) (hT : ∀ j, ‖T j‖ ≤ 1)
        (f : FiberHilbertSum E) (j : ℕ) :
        (forwardShift T hT).adjoint f j = (T j).adjoint (f (j+1)) := by
    …

    Mentions: OAI.Kaplansky.FiberHilbertSum, OAI.Kaplansky.forwardShift

  11. theorem OAI.Kaplansky.forwardShift_adjoint_single_zero line 108
  12. theorem OAI.Kaplansky.forwardShift_adjoint_single_succ line 115
  13. theorem OAI.Kaplansky.forwardShift_column line 137
  14. theorem OAI.Kaplansky.forwardShift_row_zero line 145
  15. theorem OAI.Kaplansky.forwardShift_row_succ line 150
  16. theorem OAI.Kaplansky.forwardShift_row_positive line 157
  17. theorem OAI.Kaplansky.block_norm_le_of_column line 193