Polarized Hardy--Stein identity

Krzysztof Bogdan, Michał Gutowski, Katarzyna Pietruska-Pałuba

We prove the Hardy--Stein identity for vector functions in $L^p({\mathbb{R}}^d;{\mathbb{R}}^n)$ with $1<p<\infty$ and for the canonical paring of two real functions in $L^p({\mathbb{R}}^d)$…