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Online seminář z algebry - 8.4.2021 PDF Tisk

Další seminář z algebry se koná 8.4.2021 od 13.00 online na platformě ZOOM. Informace pro připojení a další program semináře je zde.

Michael Ching

Tangent ∞-categories and Goodwillie calculus

In 1984 Rosický introduced tangent categories in order to capture axiomatically some properties of the tangent bundle functor on the category of smooth manifolds and smooth maps. Starting in 2014 Cockett and Cruttwell have developed this theory in more detail to emphasize connections with cartesian differential categories and other contexts arising from computer science and logic.

In this talk I will discuss joint work with Kristine Bauer and Matthew Burke which extends the notion of tangent category to ∞-categories. To make this generalization we use a characterization by Leung of tangent categories as modules over a symmetric monoidal category of Weil-algebras and algebra homomorphisms. Our main example of a tangent ∞-category is based on Lurie's model for the tangent bundle to an ∞-category itself. Thus we show that there is a tangent structure on the ∞-category of (differentiable) ∞-categories. This tangent structure encodes all the higher derivative information in Goodwillie's calculus of functors, and sets the scene for further applications of ideas from differential geometry to higher category theory.

Aktualizováno Pondělí, 05 Duben 2021 20:10
Online seminář z algebry - 1.4.2021 PDF Tisk

Další seminář z algebry se koná 1.4.2021 od 13.00 online na platformě ZOOM. Informace pro připojení a další program semináře je zde.

Jiří Adámek

C-Varieties of Ordered and Quantitative Algebras

Mardare, Panangaden and Plotkin introduced c-varieties of algebras on metric spaces. These are categories of metric-enriched algebras specified by equations in a context. A context puts restrictions on the distances of variables one uses. We prove that c-varieties are precisely the monadic categories over Met for countably accessible enriched monads preserving epimorphisms.

We analogously introduce c-varieties of ordered algebras as categories specified by inequalities in a context. Which means that conditions on inequalities between variables are imposed. We prove that c-varieties precisely correspond to enriched finitary monads on Pos preserving epimorphisms.

This is joint work with Jiri Rosicky.

Aktualizováno Čtvrtek, 01 Duben 2021 09:40