Q-points and Q-measures in Banach Spaces

Speaker(s)

Luis David Reyes Saenz

Affiliation

National Autonomous University of Mexico

Language of the talk

Polish

Date

April 16, 2025, 4:15 p.m.

Room

room 5050

Seminar

Topology and Set Theory Seminar

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I will talk about some recent developments regarding Q-points and Q-measures and their relation to problems in Banach space theory. In particular we will present two characterizations of Q-points: one similar to the classical Mathias' theorem for selective ultrafilters, the other one  uses the language of L-orthogonal sequences and L-orthogonal elements in Banach Spaces. We will use these characterizations as a motivation to introduce Q^+(\omega) measures and present some results that generalize known results about Q-points.
The results are consequence of joint work with Antonio Aviles, Michael Hrusak, Gonzalo Martinez-Cervantes, and Alejandro Poveda.

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