BEGIN:VCALENDAR VERSION:2.0 PRODID:-//University of Utah Math Department//Algebraic Geometry Seminar//EN CALSCALE:GREGORIAN METHOD:PUBLISH X-WR-CALNAME:Algebraic Geometry Seminar - Fall 2022 X-WR-CALDESC:Algebraic Geometry Seminar at University of Utah Mathematics Department X-WR-TIMEZONE:America/Denver BEGIN:VEVENT UID:20220831T140000-matt-baker@math.utah.edu DTSTART;TZID=America/Denver:20220831T140000 DTEND;TZID=America/Denver:20220831T150000 DTSTAMP:20260824T165309Z SUMMARY:Non-archimedean and tropical geometry, algebraic groups, moduli spaces of matroids, and the field with one element Note the unusual date & time! DESCRIPTION:Speaker: Matt Baker\, Georgia Tech\n\nI will give an introduction to Oliver Lorscheid’s theory of ordered blueprints – one of the more successful approaches to “the field of one element” – and sketch its relationship to Berkovich spaces, tropical geometry, Tits models for algebraic groups, and moduli spaces of matroids. The basic idea … LOCATION:LCB 323 URL:http://math.utah.edu/agseminar/2022-fall/ END:VEVENT BEGIN:VEVENT UID:20220906T153000-joaqu%C3%ADn-moraga@math.utah.edu DTSTART;TZID=America/Denver:20220906T153000 DTEND;TZID=America/Denver:20220906T163000 DTSTAMP:20260824T165309Z SUMMARY:Complexity and coregularity of Fano varieties DESCRIPTION:Speaker: Joaquín Moraga\, UCLA\n\nIn this talk, we discuss Fano varieties, one of the three building blocks of algebraic varieties. Among them, the most well-known class are Fano toric varieties that can be described combinatorially. In this talk, we will introduce two invariants for Fano varieties: the complexity and coregularity. … LOCATION:LCB 323 URL:http://math.utah.edu/agseminar/2022-fall/ END:VEVENT BEGIN:VEVENT UID:20220913T153000-raymond-cheng@math.utah.edu DTSTART;TZID=America/Denver:20220913T153000 DTEND;TZID=America/Denver:20220913T163000 DTSTAMP:20260824T165309Z SUMMARY:q-bic Hypersurfaces DESCRIPTION:Speaker: Raymond Cheng\, Columbia University\n\nLet’s count: 1, 2, q+1. The eponymous objects are special projective hypersurfaces of degree q+1, where q is a power of the positive ground field characteristic. This talk will sketch an analogy between the geometry of q-bic hypersurfaces and that of quadric and cubic hypersurfaces. For instance, … LOCATION:LCB 323 URL:http://math.utah.edu/agseminar/2022-fall/ END:VEVENT BEGIN:VEVENT UID:20220920T153000-lei-wu@math.utah.edu DTSTART;TZID=America/Denver:20220920T153000 DTEND;TZID=America/Denver:20220920T163000 DTSTAMP:20260824T165309Z SUMMARY:Logarithmic cotangent bundles, Chern classes, and applications DESCRIPTION:Speaker: Lei Wu\, KU Leuven\n\nUsing MacPherson's Euler obstruction function, one can identify the abelian group of constructible functions with the group of algebraic cycles on a smooth complex algebraic variety. Kashiwara's local index formula gives an alternative approach to this identification by using characteristic cycles … LOCATION:LCB 323 URL:http://math.utah.edu/agseminar/2022-fall/ END:VEVENT BEGIN:VEVENT UID:20220927T153000-pat-lank@math.utah.edu DTSTART;TZID=America/Denver:20220927T153000 DTEND;TZID=America/Denver:20220927T163000 DTSTAMP:20260824T165309Z SUMMARY:Generation of derived categories in prime characteristic DESCRIPTION:Speaker: Pat Lank\, University of South Carolina\n\nWithin this talk, which is joint work with Matthew Ballard, we will study the bounded derived category of coherent sheaves $D^b (\operatorname{coh}X)$ on an $F$-finite Noetherian scheme of prime characteristic $p$. It will be shown that $F_\ast^e (\operatorname{perf}X)$ strongly generates $D^b … LOCATION:LCB 323 URL:http://math.utah.edu/agseminar/2022-fall/ END:VEVENT BEGIN:VEVENT UID:20221004T153000-rachel-webb@math.utah.edu DTSTART;TZID=America/Denver:20221004T153000 DTEND;TZID=America/Denver:20221004T163000 DTSTAMP:20260824T165309Z SUMMARY:Hasset moduli stacks of twisted curves DESCRIPTION:Speaker: Rachel Webb\, UC Berkeley\n\nA stable n-marked curve is a nodal curve with n distinct marked points and finitely many automorphisms. If we choose rational numbers a_1, . . ., a_n in the interval (0, 1], then a weighted stable n-marked curve is a generalization where the marks are allowed to coincide as long as the total weight … LOCATION:LCB 323 URL:http://math.utah.edu/agseminar/2022-fall/ END:VEVENT BEGIN:VEVENT UID:20221018T153000-yueqiao-wu@math.utah.edu DTSTART;TZID=America/Denver:20221018T153000 DTEND;TZID=America/Denver:20221018T163000 DTSTAMP:20260824T165309Z SUMMARY:A non-Archimedean characterization of local K-stability DESCRIPTION:Speaker: Yueqiao Wu\, University of Michigan\n\nLog Fano cones are generalizations of cones over log Fano pairs, and have a local K-stability theory extending the one for log Fano pairs. In this talk, we aim to give a characterization for local K-stability from a non-Archimedean point of view, which will allow us to study general test … LOCATION:LCB 323 URL:http://math.utah.edu/agseminar/2022-fall/ END:VEVENT BEGIN:VEVENT UID:20221019T153000-lena-ji@math.utah.edu DTSTART;TZID=America/Denver:20221019T153000 DTEND;TZID=America/Denver:20221019T163000 DTSTAMP:20260824T165309Z SUMMARY:Fano hypersurfaces with no finite order birational automorphisms via the AG Preprint seminar . DESCRIPTION:Speaker: Lena Ji\, University of Michigan\n\nWe show that a very general n-dimensional complex hypersurface X of degree ≥ 5⌈(n+3)/6⌉ has no finite order birational automorphisms. In particular, this applies to higher index Fano hypersurfaces (of sufficiently high dimension). We prove this result by studying the specialization homomorphism for … LOCATION:LCB 323 URL:http://math.utah.edu/agseminar/2022-fall/ END:VEVENT BEGIN:VEVENT UID:20221025T153000-mahrud-sayrafi@math.utah.edu DTSTART;TZID=America/Denver:20221025T153000 DTEND;TZID=America/Denver:20221025T163000 DTSTAMP:20260824T165309Z SUMMARY:Short resolutions of the diagonal and a Horrocks-type splitting criterion in Picard rank 2 DESCRIPTION:Speaker: Mahrud Sayrafi\, University of Minnesota\n\nIn 1964, Horrocks proved that a vector bundle on a projective space splits as a sum of line bundles if and only if it has no intermediate cohomology. Motivated by the study of indecomposable vector bundles, in 1978 Beilinson constructed a resolution of the diagonal on P^n which has been used to … LOCATION:LCB 323 URL:http://math.utah.edu/agseminar/2022-fall/ END:VEVENT BEGIN:VEVENT UID:20221101T153000-daniel-bragg@math.utah.edu DTSTART;TZID=America/Denver:20221101T153000 DTEND;TZID=America/Denver:20221101T163000 DTSTAMP:20260824T165309Z SUMMARY:A Stacky Murphy’s Law for the Stack of Curves DESCRIPTION:Speaker: Daniel Bragg\, University of Utah\n\nWe show that every Deligne-Mumford gerbe over a field occurs as the residual gerbe of a point of the moduli stack of curves. Informally, this means that the moduli space of curves fails to be a fine moduli space in every possible way. We also show the same result for a list of other natural moduli … LOCATION:LCB 323 URL:http://math.utah.edu/agseminar/2022-fall/ END:VEVENT BEGIN:VEVENT UID:20221108T153000-justin-lacini@math.utah.edu DTSTART;TZID=America/Denver:20221108T153000 DTEND;TZID=America/Denver:20221108T163000 DTSTAMP:20260824T165309Z SUMMARY:Syzygies of adjoint linear series on projective varieties DESCRIPTION:Speaker: Justin Lacini\, University of Kansas\n\nSyzygies of algebraic varieties have long been a topic of intense interest among algebraists and geometers alike. Starting with the pioneering work of Mark Green on curves, numerous attempts have been made to extend these results to higher dimensions. Ein and Lazarsfeld proved that if A is a very … LOCATION:LCB 323 URL:http://math.utah.edu/agseminar/2022-fall/ END:VEVENT BEGIN:VEVENT UID:20221118T153000-philip-engel@math.utah.edu DTSTART;TZID=America/Denver:20221118T153000 DTEND;TZID=America/Denver:20221118T163000 DTSTAMP:20260824T165309Z SUMMARY:Elliptic surfaces and a Torelli theorem Note the unusual date! DESCRIPTION:Speaker: Philip Engel\, University of Georgia\n\nElliptic surfaces fibering over an elliptic curve with 12 singular fibers form a ten-dimensional moduli space. Their middle cohomology has a K3 type Hodge structure endowing the moduli space with a period map into a ten-dimensional arithmetic quotient. I will discuss a proof that this period map is … LOCATION:LCB 323 URL:http://math.utah.edu/agseminar/2022-fall/ END:VEVENT BEGIN:VEVENT UID:20221129T153000-emelie-arvidsson@math.utah.edu DTSTART;TZID=America/Denver:20221129T153000 DTEND;TZID=America/Denver:20221129T163000 DTSTAMP:20260824T165309Z SUMMARY:Properties of log-canonical threefold singularities in positive characteristics DESCRIPTION:Speaker: Emelie Arvidsson\, University of Utah\n\nIn this talk I will study if some well—known properties of log canonical threefold singularities over the complex numbers hold true over perfect fields of positive characteristics? For surfaces of Fano type the Kawamata–Viehweg vanishing theorem, which in general famously fails in positive … LOCATION:LCB 323 URL:http://math.utah.edu/agseminar/2022-fall/ END:VEVENT BEGIN:VEVENT UID:20221206T153000-kimoi-kemboi@math.utah.edu DTSTART;TZID=America/Denver:20221206T153000 DTEND;TZID=America/Denver:20221206T163000 DTSTAMP:20260824T165309Z SUMMARY:Full strong exceptional collections on rank-two linear GIT quotients DESCRIPTION:Speaker: Kimoi Kemboi\, Cornell University\n\nA full strong exceptional collection is an important structure to have on a derived category with many useful implications. For instance, such a collection produces a basis for the Grothendieck group and a tilting object. In this talk, we will discuss the existence of full strong exceptional … LOCATION:LCB 323 URL:http://math.utah.edu/agseminar/2022-fall/ END:VEVENT END:VCALENDAR