High-contrast homogenization: Provider.Response.DiagonalWeakOptimizerStationarity #
Imported from the Apache-2.0 HighContrastHomogenization development at commit
7a13dbcd8d6609264a713373f5c69ceeac870472.
Stationarity of aligned optimizer averages #
Aligned and centered optimizer averages differ only by sample translation. Stationarity and the mean-one cutoff therefore cancel their weighted means.
theorem
HCPolySupport.HighContrast.Response.exists_blockCellAverage_diagonalWeakChildState_subSkew_eq_translateCoeff
{d : ℕ}
{l s : ℤ}
{q : Mat d}
(hgrid : IsRoundedGrid l q)
(hls : l ≤ s)
(w : Fin d → ℤ)
(g : Mat d)
(hg : IsSkewMat g)
(p r : Vec d)
:
∃ (z : Fin d → ℤ),
(adaptedCellCenter q s w = fun (i : Fin d) => ↑(z i)) ∧ ∀ (a : CoeffSpace d),
blockCellAverage (adaptedCellAt q s w) (diagonalWeakChildState ⋯ s w (a.subSkew g hg) p r) = blockCellAverage (adaptedCell q s) (diagonalWeakState ⋯ s ((translateCoeff z a).subSkew g hg) p r)
Constant-skew recentering preserves aligned translation covariance.
theorem
HCPolySupport.HighContrast.Response.exists_blockCellAverage_diagonalWeakChildState_adjointSubSkew_eq_translateCoeff
{d : ℕ}
{l s : ℤ}
{q : Mat d}
(hgrid : IsRoundedGrid l q)
(hls : l ≤ s)
(w : Fin d → ℤ)
(g : Mat d)
(hg : IsSkewMat g)
(p r : Vec d)
:
∃ (z : Fin d → ℤ),
(adaptedCellCenter q s w = fun (i : Fin d) => ↑(z i)) ∧ ∀ (a : CoeffSpace d),
blockCellAverage (adaptedCellAt q s w) (diagonalWeakChildState ⋯ s w (a.subSkew g hg).transpose p r) = blockCellAverage (adaptedCell q s) (diagonalWeakState ⋯ s ((translateCoeff z a).subSkew g hg).transpose p r)
The recentered adjoint optimizer has its own aligned covariance.
theorem
HCPolySupport.HighContrast.Response.avsum_one_sub_cutoffAverage_mul_integral_childState_subSkew_eq_zero
{d : ℕ}
[NeZero d]
{P : MeasureTheory.Measure (CoeffSpace d)}
[MeasureTheory.IsProbabilityMeasure P]
(hstat : IsStationaryLaw P)
{l s t : ℤ}
{q : Mat d}
(hgrid : IsRoundedGrid l q)
(hls : l ≤ s)
(hst : s ≤ t)
(hint : HasFiniteAdaptedMean P q s)
(g : Mat d)
(hg : IsSkewMat g)
(p r : Vec d)
(α : BlockCoord d)
:
(avsum (alignedIndex q s t) fun (w : Fin d → ℤ) =>
(1 - volumeAverage (adaptedCellAt q s w) (adaptedPreYoungCutoff q ⋯ t)) * ∫ (a : CoeffSpace d), toFullBlockVec (blockCellAverage (adaptedCellAt q s w) (diagonalWeakChildState ⋯ s w (a.subSkew g hg) p r))
α ∂P) = 0
The same cancellation holds for the literal constant-skew primal state.
theorem
HCPolySupport.HighContrast.Response.avsum_one_sub_cutoffAverage_mul_integral_childState_adjointSubSkew_eq_zero
{d : ℕ}
[NeZero d]
{P : MeasureTheory.Measure (CoeffSpace d)}
[MeasureTheory.IsProbabilityMeasure P]
(hstat : IsStationaryLaw P)
{l s t : ℤ}
{q : Mat d}
(hgrid : IsRoundedGrid l q)
(hls : l ≤ s)
(hst : s ≤ t)
(hint : HasFiniteAdaptedMean P q s)
(g : Mat d)
(hg : IsSkewMat g)
(p r : Vec d)
(α : BlockCoord d)
:
(avsum (alignedIndex q s t) fun (w : Fin d → ℤ) =>
(1 - volumeAverage (adaptedCellAt q s w) (adaptedPreYoungCutoff q ⋯ t)) * ∫ (a : CoeffSpace d), toFullBlockVec
(blockCellAverage (adaptedCellAt q s w) (diagonalWeakChildState ⋯ s w (a.subSkew g hg).transpose p r)) α ∂P) = 0
The literal constant-skew adjoint state has the independent cancellation.