Bilin Form Integrand mul smooth eq
DeGiorgi.bilinFormIntegrand_mul_smooth_eq
Plain-language statement
Pointwise expansion of the bilinear-form integrand against a smooth-product witness η · w. The weak gradient of η · w is η · ∇w + (∇η) · w (from mul_smooth_bounded_p), so the bilinear-form integrand is: ⟪A∇u, ∇(η·w)⟫ = η · ⟪A∇u, ∇w⟫ + w · ⟪A∇u, ∇η⟫ where ∇η is encoded as the vector with components (fderiv ℝ η x)(single i 1). Note: this...
Source project: DeGiorgi
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