Calf is the junior COW.
The principal organisers are Aurelio Carlucci (Oxford) and Lorenzo de Biase (Cardiff), and local organisers include Alice Cuzzucoli and Jake Patel (Warwick), Ben Morley (Cambridge), and Karoline Van Gemst (Birmingham). Calf announcements are made using the COW mailing list. If you would like to get involved in the organisation, or suggest your institution as the next venue, please contact any of the people above.
The COW seminar has some funds for travel expenses, and information on how to claim a reimbursement can be found on the official COW webpage.
|University of Birmingham (Nuffield Building) - Friday 5th April 2019|
|Nebojsa Pavic (Sheffield)||13:00||Room G13||Quotient singularities and Grothendieck groups|
|Abstract:||We study the K-groups of the singularity category for quasi-projective schemes. Particularly, we show for isolated quotient singularities that the Grothendieck group of the singularity category is finite torsion and that rational Poincare duality is satisfied on the level of Grothendieck groups. We consider also consequences for the resolution of singularities of such quotient singularities and study dual properties in this setting. More concretely, we prove a conjecture of Bondal and Orlov in the case of (not necessarily isolated) quotient singularities.|
|Giulia Gugiatti (LSGNT)||15:00||Room G13||Hyperelliptic integrals and mirrors of the Johnson-Kollár del Pezzo surfaces|
|Abstract:||In this talk I will consider the regularised I-function of the family of del Pezzo surfaces of degree 8k+4 in P(2,2k+1,2k+1,4k+1), first constructed by Johnson and Kollár, and I will ask the following two equivalent questions: 1) Is this function a period of a pencil of curves? 2) Does the family admit a Landau-Ginzburg (LG) mirror? After some background on the Fano-LG correspondence, I will explain why these two questions are interesting on their own, and I will give a positive answer to them by explicitly constructing a pencil of hyperelliptic curves of genus 3k+1 as a LG mirror. To conclude, I will sketch how to find this pencil starting from the work of Beukers, Cohen and Mellit on hypergeometric functions. This is a joint work with Alessio Corti.|
|James Plowman (Warwick)||16:30||Room G13||The Witt complex of a scheme with a dualising complex.|
|Abstract:||The Witt complex of a scheme can be thought of as the negative part of a Grothendieck-Witt analogue to the Gersten resolution of algebraic K-theory. Grothendieck-Witt theory can be described as K-theory "with duality" - and direct constructions of Witt complexes rely upon careful manipulation of the local dualising objects involved. The main aim of this talk is to present a construction of a Witt complex in greater generality than is currently available in the literature by extracting the local dualities required from residual complexes - which are the minimal injective resolutions of dualising complexes.|
|Further information about the venue and social events will be published shortly.|