Dear all, We are pleased to announce the Brazilian Category Theory seminars of this semester, with monthly talks. We invite everyone to join us for our next meeting, which will take place next Monday, September 28, at 4:00 PM (SP time). Fernando Yamauti (USP) September 28, 2026 – 4:00 PM (SP time) Online at: https://meet.google.com/ruk-zppv-jtu Title: Topoi and Homotopy Types Abstract: The main result of the classic monograph "Classifying Spaces and Classifying Topoi" by Moerdijk states that presheaf topoi C^ present the homotopy type of the classifying space BC. I will present a new proof for general (oo,1)-topoi as well as point some consequences of the localisation techniques used in this proof. If time remains, I will point some ongoing work on computations of related localisations of the category Topos. For more information about other seminars, events, and category theory projects in Brazil, visit our website: https://categorias-brasil.github.io/. Best regards Anny Azevedo