Property $(F{L}_p)$ implies property $(F{L}_q)$ for $1<q<p<\infty$

Abstract

It is known that for $\sigma$-compact groups Kazhdan's Property $(T)$ is equivalent to Serre's Property $(FH)$. Generalized versions of those properties, called properties $(T_B)$ and $(F_B)$, can be defined in terms of the isometric representations of a group on an arbitrary Banach space $B$. Property $(F_B)$ implies $(T_B)$. It is known that a group with Property $(T_{l_p})$ shares some properties with Kazhdan's groups, for example compact generation and compact abelianization. Moreover in the case of discrete groups, Property $(T_{l_p})$ implies Lubotzky's Property $(\tau )$. In this paper we prove that in the case of discrete groups and $1<p<q<\infty$ and $p\ne 2$, Property $(F_{l_q})$ implies Property $(F_{l_p})$.