OAI/GroupTheory/Kervaire/ScalarPhase.lean

GitHub source file

23 declarations, 0 contain sorry, 0 declared as axioms

  1. def OAI.KervaireScalarPhase.phase line 17
  2. theorem OAI.KervaireScalarPhase.phase_one line 19
  3. theorem OAI.KervaireScalarPhase.phase_nonneg line 21
  4. theorem OAI.KervaireScalarPhase.phase_lt_one line 23
  5. theorem OAI.KervaireScalarPhase.measurable_phase line 25
  6. theorem OAI.KervaireScalarPhase.phase_exp line 28
  7. theorem OAI.KervaireScalarPhase.phase_exp_normalized line 37
  8. def OAI.KervaireScalarPhase.cutApproach line 44

    Source documentation

    Tangential approach to the phase cut, from the prescribed side.

    def cutApproach (ε : ℝ) : ℂ := (1 - ε ^ 2 : ℝ) + ε * Complex.I
  9. theorem OAI.KervaireScalarPhase.norm_cutApproach_lt_one line 46
  10. theorem OAI.KervaireScalarPhase.exp_two_arg line 57

    Source documentation

    The polar angle encoded by a doubled exponential.

    theorem exp_two_arg (x : ℂ) (hx : x ≠ 0) :
        Complex.exp ((2 * x.arg : ℝ) * Complex.I) = x / star x := by
    …
  11. theorem OAI.KervaireScalarPhase.phase_eq_arg_one_sub line 73

    Source documentation

    Exact scalar phase away from its cut, expressed by the logarithm in the disk.

    theorem phase_eq_arg_one_sub {z : ℂ} (hz : ‖z‖ = 1) (hz' : z ≠ 1) :
        phase z = 1 / 2 + (1 - z).arg / Real.pi := by
    …

    Mentions: OAI.KervaireScalarPhase.phase

  12. def OAI.KervaireScalarPhase.smoothPhase line 121

    Source documentation

    The regularization used in the trace inequality.

    def smoothPhase (a z : ℂ) : ℝ := 1 / 2 + (1 - a * z).arg / Real.pi
  13. theorem OAI.KervaireScalarPhase.re_one_sub_mul_pos line 123
  14. theorem OAI.KervaireScalarPhase.smoothPhase_mem_Icc line 129
  15. theorem OAI.KervaireScalarPhase.re_one_sub_pos line 140
  16. theorem OAI.KervaireScalarPhase.tendsto_smoothPhase_cut line 152

    Source documentation

    The tangential limit agrees with the discontinuous phase, also at one.

    theorem tendsto_smoothPhase_cut {z : ℂ} (hz : ‖z‖ = 1) :
        Tendsto (fun ε : ℝ => smoothPhase (cutApproach ε) z)
          (𝓝[>] 0) (𝓝 (phase z)) := by
    …

    Mentions: OAI.KervaireScalarPhase.smoothPhase, OAI.KervaireScalarPhase.cutApproach, OAI.KervaireScalarPhase.phase

  17. theorem OAI.KervaireScalarPhase.smoothPhase_eq_series line 191

    Source documentation

    The Mercator sum realizes the same real phase regularization.

    theorem smoothPhase_eq_series {a z : ℂ} (haz : ‖a * z‖ < 1) :
        smoothPhase a z = 1 / 2 -
          (∑' n : ℕ, (a * z) ^ (n+1) / (n+1)).im / Real.pi := by
    …

    Mentions: OAI.KervaireScalarPhase.smoothPhase

  18. def OAI.KervaireScalarPhase.cutTime line 198

    Source documentation

    A concrete sequence in the open disk approaching the required side of the cut.

    def cutTime (n : ℕ) : ℝ := 1 / ((n : ℝ) + 2)
  19. theorem OAI.KervaireScalarPhase.cutTime_pos line 200
  20. theorem OAI.KervaireScalarPhase.cutTime_lt_one line 204
  21. theorem OAI.KervaireScalarPhase.tendsto_cutTime line 210
  22. theorem OAI.KervaireScalarPhase.norm_cutApproach_cutTime_lt_one line 218
  23. theorem OAI.KervaireScalarPhase.tendsto_smoothPhase_cutTime line 221