On the interpolation constant for subadditive operators in Orlicz spaces

Alexei Yu. Karlovich, Lech Maligranda

Let $1\le p<q\le \infty$ and let $T$ be a subadditive operator acting on $L^p$ and $L^q$. We prove that $T$ is bounded on the Orlicz space $L^{\varphi }$, where $ϕ^{-1}(u)=u^{1/p}ρ(u^{1/q-1/…