10 papers
Unconditional bases and Daugavet renormings
Rainis Haller, Johann Langemets, Yoël Perreau +1
We introduce a new diametral notion for points of the unit sphere of Banach spaces, that naturally complements the notion of Delta-points, but is weaker than the notion of Daugavet…
Transfinite almost square Banach spaces
Antonio Avilés, Stefano Ciaci, Johann Langemets +2
It is known that a Banach space contains an isomorphic copy of if, and only if, it can be equivalently renormed to be almost square. We introduce and study transfinite versio…
Attaining strong diameter two property for infinite cardinals
Stefano Ciaci, Johann Langemets, Aleksei Lissitsin
We extend the (attaining of) strong diameter two property to infinite cardinals. In particular, a Banach space has the 1-norming attaining strong diameter two property with respect…
A characterization of Banach spaces containing via ball-covering properties
Stefano Ciaci, Johann Langemets, Aleksei Lissitsin
In 1989, G. Godefroy proved that a Banach space contains an isomorphic copy of if and only if it can be equivalently renormed to be octahedral. It is known that octahedral…
On Daugavet indices of thickness
Rainis Haller, Johann Langemets, Vegard Lima +2
Inspired by R. Whitley's thickness index the last named author recently introduced the Daugavet index of thickness of Banach spaces. We continue the investigation of the behavior o…
Symmetric strong diameter two property in tensor products of Banach spaces
Johann Langemets
We continue the investigation of the behaviour of diameter two properties in tensor products of Banach spaces. Our main result shows that the symmetric strong diameter two property…