13.30 Karin M Jacobsen

What are triangulations in the surface model?

To any gentle algebra we can associate an oriented marked surface with a dissection, giving us a geometric model of the bounded derived category, where curves taken up to homotopy correspond to indecomposable objects.

In joint work with Haugland, Schiffler and Schroll, we investigate the natural question: What do the triangulations of such a surface correspond to?

In answering the question, we arrive at a definition of maximal almost rigid subcategories in the bounded derived category. Furthermore we study interplay between algebraic and geometric mutation.

14.45 Sofia Franchini

A discrete cluster category having a negative Calabi-Yau parameter

Igusa-Todorov discrete cluster categories are an infinite discrete generalisation of the classical cluster category of type A. These are triangulated categories having 2 Calabi-Yau dimension, i.e. their Ext spaces are symmetric.

Our aim is to introduce a (-1)-Calabi-Yau version of Igusa-Todorov discrete cluster categories. To do so, we define the category of infinite discrete symmetric Nakayama representations by using the notion of continuous Nakayama representations introduced by Rock and Zhu.

16.00 Greg Stevenson

Grothendieck categories: a survey

I'll give an introduction to Grothendieck categories and discuss some of their good properties. Some of these are well known, for instance the Gabriel–Popescu theorem, but others, such as the behaviour of the collection of localizations, are less well known.

Tea, coffee and cake will be provided.