Disjointification inequalities for Hoeffding subspaces of $H^1$ on an infinite polydisc

Abstract

We prove that the $L^1$ norm on the linear span of functions on $\T^\N$ dependent on $m$ variables and analytic and mean zero in each of them can be expressed as an interpolation sum of $H^1\left(\mathbb{T}^S,\ell^1\left(\mathbb{N}^S,H^2\left(\mathbb{T}^{[1,m]\setminus S},\ell^2\left(\mathbb{N}^{[1,m]\setminus S}\right)\right)\right)\right)$ norms over $S\subseteq [1,m]$ and derive some interpolation consequences.