3 papers
math.FA2026
A counterexample for the Daugavet index of thickness in -sums
Rainis Haller, Andre Ostrak
We give a negative answer to a question of Haller-Langemets-Lima-Nadel-Rueda Zoca asking whether, for all Banach spaces and , the Daugavet index of thickness satisfies \[ T(…
math.FA2025
Duality of Lipschitz-free spaces over ultrametric spaces
Trond A. Abrahamsen, Vegard Lima, Andre Ostrak
We give a metric characterisation of when the Lipschitz-free space over a separable ultrametric space is a dual Banach space. In the case where the Lipschitz-free space has a predu…
math.FA2025
The local diameter two property and the diameter two property in spaces of Lipschitz functions
Rainis Haller, Jaan Kristjan Kaasik, Andre Ostrak
We separate the local diameter two property from the diameter two property and their weak-star counterparts from each other in spaces of Lipschitz functions. We characterise the $w…