Daugavet- And Delta-Points In Absolute Sums Of Banach Spaces

A Daugavet-point (resp. Delta-point) of a Banach space is a norm one element x for which every point in the unit ball (resp. element x itself) is in the closed convex hull of unit ball elements that are almost at distance 2 from x. A Banach space has the well-known Daugavet property (resp. diametral local diameter 2 property) if and only if every norm one element is a Daugavet-point (resp. Delta-point). Our results complement the ones of T. A. Abrahamsen, R. Haller, V. Lima and K. Pirk [Delta- and Daugavet-points in Banach spaces, Proc. Edinb. Math. Soc. 63/2 (2020) 475-496] concerning the existence of Daugavet- and Delta-points in absolute sums of Banach spaces.