Hölder’s means and fixed points for multivalued nonexpansive mappings

Abstract

In this paper, we show some geometric conditions on Banach spaces by considering Hölder's means and many well known parameters namely the James constant, the von Neumann-Jordan constant, the weakly convergent sequence coefficient, the normal structure coefficient, the coefficient of weak orthogonality, which imply the existence of fixed points for multivalued nonexpansive mappings and normal structure of Banach spaces. Some of our main results improve and generalize several known results in the recent literature on this topic. We also show that some of our results are sharp.

On a General Class of Geometric Constants and Normal Structure in Banach Spaces

“…Since then, many mathematicians have established that, under various geometric properties of a Banach space often measured by different geometric constants, normal structure or uniform normal structure of the space is guaranteed. For more details in this direction, we refer the reader to [10,11,12,13,14,15,16,17,21,25,28,29,30,31,32,36] and the references mentioned therein.…”