The algebraic delta invariant, a number encoding the K-stability of a Fano variety, is a central theme of this Winter school. In the first lecture, T. Delcroix presents an analytic viewpoint on the delta invariant developped by Kewei Zhang, along with the rough ideas of the variational approach to existence of canonical Kähler metrics. In his second lecture, he extends this to the weighted Kähler setting (joint work with S. Jubert), allowing to deal with Kähler-Ricci solitons and more. [-]

The algebraic delta invariant, a number encoding the K-stability of a Fano variety, is a central theme of this Winter school. In the first lecture, T. Delcroix presents an analytic viewpoint on the delta invariant developped by Kewei Zhang, along with the rough ideas of the variational approach to existence of canonical Kähler metrics. In his second lecture, he extends this to the weighted Kähler setting (joint work with S. Jubert), allowing to deal with Kähler-Ricci solitons and more. [-]

Reid's recipe is an equivalent of the McKay correspondence in dimension three. It marks interior line segments and lattice points in the fan of the G-Hilbert scheme (a specific crepant resolution of $\mathbb{C}^{3} / G$ for $G \subset S L(3, \mathbb{C})$ ) with characters of irreducible representations of $G$. Our goal is to generalise this by marking the toric fan of a crepant resolution of any affine Gorenstein singularity, in a way that is compatible with both the G-Hilbert case and its categorical counterpart known as Derived Reid's Recipe. To achieve this, we foray into the combinatorial land of quiver moduli spaces and dimer models. This is joint work with Alastair Craw and Jesus Tapia Amador.[-]