Dear all, The next Banach spaces webinar is on Friday August 7 9AM CDT (e.g., Dallas, TX time). Please join us at https://unt.zoom.us/j/512907580 Speaker: Pete Casazza (University of Missouri) Title: Tsirelson space, explicitly definable Banach space, implicitly definable Banach space Abstract. We prove that Tsirelson's space cannot be defined explicitly from the classical Banach sequence spaces. We also prove that any Banach space that is explicitly definable from a class of spaces that contain $\ell_p$ or $c_0$ must contain $\ell_p$ or $c_0$ as well. * For more information about the past and future talks, and videos please visit the webinar website http://www.math.unt.edu/~bunyamin/banach Upcoming schedule August 14: Robert Young (NYU) Thank you, and best regards, Bunyamin Sari