Daugavet points and $\Delta$-points in Lipschitz-free spaces

Abstract

We study Daugavet points and $\Delta$-points in Lipschitz-free Banach spaces. We prove that, if $M$ is a compact metric space, then $\mu \in S_{\mathcal{F}(M)}$ is a Daugavet point if, and only if, there is no denting point of $B_{\mathcal{F}(M)}$ at distance strictly smaller than two from $\mu$. Moreover, we prove that if $x$ and $y$ are connectable by rectifiable curves of lenght as close to $d(x,y)$ as we wish, then the molecule $m_{x,y}$ is a $\Delta$-point. Some conditions on $M$ which guarantee that the previous implication reverses are also obtained. As a consequence of our work, we show that Lipschitz-free spaces are natural examples of Banach spaces where we can guarantee the existence of $\Delta$-points which are not Daugavet points.

arXiv comment19 pages