AutoSamplingTheory.TechnicalLemmas.Measure.DisplacementDerivativeDetPos
6 named declarations scanned from AutoSamplingTheory/TechnicalLemmas/Measure/DisplacementDerivativeDetPos.lean.
Declarations
theorem AutoSamplingTheory.TechnicalLemmas.Measure.DisplacementDerivativeDetPos.toMatrix_affineDisplacementDerivative_posDef Partial Not mapped
- An SPD matrix representation of the endpoint derivative gives an SPD matrix representation of the affine displacement derivative on the full segment.
theorem toMatrix_affineDisplacementDerivative_posDef
(b : Module.Basis ι ℝ E) (T' : E →L[ℝ] E)
(hT : (LinearMap.toMatrix b b T'.toLinearMap).PosDef)
(t : ℝ) (ht0 : 0 ≤ t) (ht1 : t ≤ 1) :
(LinearMap.toMatrix b b
(affineDisplacementDerivative T' t).toLinearMap).PosDef := by
rw [toMatrix_affineDisplacementDerivative]
exact affineIdentityMatrix_posDef
(LinearMap.toMatrix b b T'.toLinearMap) hT t ht0 ht1
/-- A PSD endpoint derivative is already enough for strict positivity of the
interior affine derivative matrix. -/
AutoSamplingTheory/TechnicalLemmas/Measure/DisplacementDerivativeDetPos.lean:39published source at 0e31a3cda412
theorem AutoSamplingTheory.TechnicalLemmas.Measure.DisplacementDerivativeDetPos.toMatrix_affineDisplacementDerivative_posDef_of_posSemidef Partial Not mapped
- A PSD endpoint derivative is already enough for strict positivity of the interior affine derivative matrix.
theorem toMatrix_affineDisplacementDerivative_posDef_of_posSemidef
(b : Module.Basis ι ℝ E) (T' : E →L[ℝ] E)
(hT : (LinearMap.toMatrix b b T'.toLinearMap).PosSemidef)
(t : ℝ) (ht0 : 0 ≤ t) (ht1 : t < 1) :
(LinearMap.toMatrix b b
(affineDisplacementDerivative T' t).toLinearMap).PosDef := by
rw [toMatrix_affineDisplacementDerivative]
exact affineIdentityMatrix_posDef_of_posSemidef
(LinearMap.toMatrix b b T'.toLinearMap) hT t ht0 ht1
/-- Under an SPD endpoint derivative, the continuous-linear determinant of the
affine displacement derivative is strictly positive. -/
AutoSamplingTheory/TechnicalLemmas/Measure/DisplacementDerivativeDetPos.lean:51published source at 0e31a3cda412
theorem AutoSamplingTheory.TechnicalLemmas.Measure.DisplacementDerivativeDetPos.det_affineDisplacementDerivative_pos Partial Not mapped
- Under an SPD endpoint derivative, the continuous-linear determinant of the affine displacement derivative is strictly positive.
theorem det_affineDisplacementDerivative_pos
(b : Module.Basis ι ℝ E) (T' : E →L[ℝ] E)
(hT : (LinearMap.toMatrix b b T'.toLinearMap).PosDef)
(t : ℝ) (ht0 : 0 ≤ t) (ht1 : t ≤ 1) :
0 < LinearMap.det (affineDisplacementDerivative T' t).toLinearMap := by
rw [det_affineDisplacementDerivative_eq_matrix_det b T' t]
exact (affineIdentityMatrix_posDef
(LinearMap.toMatrix b b T'.toLinearMap) hT t ht0 ht1).det_pos
/-- Interior-time determinant positivity from the weaker PSD endpoint
hypothesis. -/
AutoSamplingTheory/TechnicalLemmas/Measure/DisplacementDerivativeDetPos.lean:63published source at 0e31a3cda412
theorem AutoSamplingTheory.TechnicalLemmas.Measure.DisplacementDerivativeDetPos.det_affineDisplacementDerivative_pos_of_posSemidef Partial Not mapped
- Interior-time determinant positivity from the weaker PSD endpoint hypothesis.
theorem det_affineDisplacementDerivative_pos_of_posSemidef
(b : Module.Basis ι ℝ E) (T' : E →L[ℝ] E)
(hT : (LinearMap.toMatrix b b T'.toLinearMap).PosSemidef)
(t : ℝ) (ht0 : 0 ≤ t) (ht1 : t < 1) :
0 < LinearMap.det (affineDisplacementDerivative T' t).toLinearMap := by
rw [det_affineDisplacementDerivative_eq_matrix_det b T' t]
exact (affineIdentityMatrix_posDef_of_posSemidef
(LinearMap.toMatrix b b T'.toLinearMap) hT t ht0 ht1).det_pos
/-- The absolute determinant in change of variables is redundant under an SPD
endpoint derivative. -/
AutoSamplingTheory/TechnicalLemmas/Measure/DisplacementDerivativeDetPos.lean:74published source at 0e31a3cda412
theorem AutoSamplingTheory.TechnicalLemmas.Measure.DisplacementDerivativeDetPos.abs_det_affineDisplacementDerivative_eq Partial Not mapped
- The absolute determinant in change of variables is redundant under an SPD endpoint derivative.
theorem abs_det_affineDisplacementDerivative_eq
(b : Module.Basis ι ℝ E) (T' : E →L[ℝ] E)
(hT : (LinearMap.toMatrix b b T'.toLinearMap).PosDef)
(t : ℝ) (ht0 : 0 ≤ t) (ht1 : t ≤ 1) :
|LinearMap.det (affineDisplacementDerivative T' t).toLinearMap| =
LinearMap.det (affineDisplacementDerivative T' t).toLinearMap :=
abs_of_pos (det_affineDisplacementDerivative_pos b T' hT t ht0 ht1)
/-- Interior-time absolute-determinant removal from a PSD endpoint derivative. -/
AutoSamplingTheory/TechnicalLemmas/Measure/DisplacementDerivativeDetPos.lean:85published source at 0e31a3cda412
theorem AutoSamplingTheory.TechnicalLemmas.Measure.DisplacementDerivativeDetPos.abs_det_affineDisplacementDerivative_eq_of_posSemidef Partial Not mapped
- Interior-time absolute-determinant removal from a PSD endpoint derivative.
theorem abs_det_affineDisplacementDerivative_eq_of_posSemidef
(b : Module.Basis ι ℝ E) (T' : E →L[ℝ] E)
(hT : (LinearMap.toMatrix b b T'.toLinearMap).PosSemidef)
(t : ℝ) (ht0 : 0 ≤ t) (ht1 : t < 1) :
|LinearMap.det (affineDisplacementDerivative T' t).toLinearMap| =
LinearMap.det (affineDisplacementDerivative T' t).toLinearMap :=
abs_of_pos
(det_affineDisplacementDerivative_pos_of_posSemidef b T' hT t ht0 ht1)
end
end DisplacementDerivativeDetPos
end Measure
end TechnicalLemmas
end AutoSamplingTheory
AutoSamplingTheory/TechnicalLemmas/Measure/DisplacementDerivativeDetPos.lean:94published source at 0e31a3cda412