BEGIN:VCALENDAR
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PRODID:-//Center for Complex Geometry - ECPv6.16.3//NONSGML v1.0//EN
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METHOD:PUBLISH
X-ORIGINAL-URL:https://ccg.ibs.re.kr
X-WR-CALDESC:Events for Center for Complex Geometry
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X-Robots-Tag:noindex
X-PUBLISHED-TTL:PT1H
BEGIN:VTIMEZONE
TZID:Asia/Seoul
BEGIN:STANDARD
TZOFFSETFROM:+0900
TZOFFSETTO:+0900
TZNAME:KST
DTSTART:20210101T000000
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END:VTIMEZONE
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20220118T110000
DTEND;TZID=Asia/Seoul:20220118T120000
DTSTAMP:20260615T043905
CREATED:20220118T020000Z
LAST-MODIFIED:20211213T012913Z
UID:959-1642503600-1642507200@ccg.ibs.re.kr
SUMMARY:Kento Fujita\, The Calabi Problem for Fano Threefolds
DESCRIPTION:     Speaker\n\n\nKento Fujita\nOsaka Univ.\n\n\n\n\n\n\nThere are 105 irreducible families of smooth Fano threefolds\, which have been classified by Iskovskikh\, Mori and Mukai. For each family\, we determine whether its general member admits a Kähler-Einstein metric or not. This is a joint work with Carolina Araujo\, Ana-Maria Castravet\, Ivan Cheltsov\, Anne-Sophie Kaloghiros\, Jesus Martinez-Garcia\, Constantin Shramov\, Hendrik Suess and Nivedita Viswanathan.
URL:https://ccg.ibs.re.kr/event/2022-01-18/
LOCATION:on-line
CATEGORIES:Algebraic Geometry Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20220119T100000
DTEND;TZID=Asia/Seoul:20220119T120000
DTSTAMP:20260615T043905
CREATED:20220119T010000Z
LAST-MODIFIED:20211227T043507Z
UID:910-1642586400-1642593600@ccg.ibs.re.kr
SUMMARY:Han-Bom Moon\, Derived Category of Moduli of Vector Bundles I
DESCRIPTION:     Speaker\n\n\nHan-Bom Moon\nFordham University\n\n\n\n\n\nThe derived category of a smooth projective variety is an object expected to encode much birational geometric information. Recently\, there have been many results on decomposing derived categories into simpler building blocks. In the first lecture\, I will provide an elementary introduction to two independent topics — 1. the definition and basic properties of the derived category and 2. moduli spaces of vector bundles on a curve. In the second lecture\, I will present recent progress on the structure of the derived category of the moduli space. Most of the lectures will be accessible to graduate students with basic knowledge of algebraic geometry. The second lecture is based on ongoing joint work with Kyoung-Seog Lee.
URL:https://ccg.ibs.re.kr/event/2022-01-19/
LOCATION:TBA
CATEGORIES:Complex Geometry Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20220120T110000
DTEND;TZID=Asia/Seoul:20220120T120000
DTSTAMP:20260615T043905
CREATED:20220120T020000Z
LAST-MODIFIED:20211227T043533Z
UID:991-1642676400-1642680000@ccg.ibs.re.kr
SUMMARY:Han-Bom Moon\, Derived Category of Moduli of Vector Bundles II
DESCRIPTION:     Speaker\n\n\nHan-Bom Moon\nFordham University\n\n\n\n\n\nThe derived category of a smooth projective variety is an object expected to encode much birational geometric information. Recently\, there have been many results on decomposing derived categories into simpler building blocks. In the first lecture\, I will provide an elementary introduction to two independent topics — 1. the definition and basic properties of the derived category and 2. moduli spaces of vector bundles on a curve. In the second lecture\, I will present recent progress on the structure of the derived category of the moduli space. Most of the lectures will be accessible to graduate students with basic knowledge of algebraic geometry. The second lecture is based on ongoing joint work with Kyoung-Seog Lee.
URL:https://ccg.ibs.re.kr/event/2022-01-20/
LOCATION:TBA
CATEGORIES:Complex Geometry Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20220125T150000
DTEND;TZID=Asia/Seoul:20220125T160000
DTSTAMP:20260615T043905
CREATED:20220125T060000Z
LAST-MODIFIED:20220107T014952Z
UID:979-1643122800-1643126400@ccg.ibs.re.kr
SUMMARY:Sanghoon Baek\, Relationship between the Chow and Grothendieck Rings for Generic Flag Varieties
DESCRIPTION:     Speaker\n\n\nSanghoon Baek\nKAIST\n\n\n\n\n\nConsider the canonical morphism from the Chow ring of a smooth variety X to the associated graded ring of the coniveau filtration on the Grothendieck ring of X. In general\, this morphism is not injective. However\, Nikita Karpenko conjectured that these two rings are isomorphic for a generic flag variety X of a semisimple group G\, where he confirmed the conjecture for a simple group G of type A or C. Recently\, this conjecture was disproved by Nobuaki Yagita for some spin groups G. We will discuss further counter-examples using the K-theoretical Pieri formula for highest orthogonal grassmannians. This is joint work with Nikita Karpenko.
URL:https://ccg.ibs.re.kr/event/2022-01-25-1500/
LOCATION:B266\, IBS\, Korea\, Republic of
CATEGORIES:Algebraic Geometry Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20220125T162000
DTEND;TZID=Asia/Seoul:20220125T172000
DTSTAMP:20260615T043905
CREATED:20220125T072000Z
LAST-MODIFIED:20220112T014905Z
UID:981-1643127600-1643131200@ccg.ibs.re.kr
SUMMARY:Rostislav Devyatov\, Multiplicity-free Products of Schubert Divisors and an Application to Canonical Dimension
DESCRIPTION:     Speaker\n\n\nRostislav Devyatov\nKAIST\n\n\n\n\n\n\nIn the first part of my talk I am going to speak about Schubert calculus. Let G/B be a flag variety\, where G is a linear simple algebraic group\, and B is a Borel subgroup. Schubert calculus studies (in classical terms) multiplication in the cohomology ring of a flag variety over the complex numbers\, or (in more algebraic terms) the Chow ring of the flag variety. This ring is generated as a group by the classes of so-called Schubert varieties (or their Poincare duals\, if we speak about the classical cohomology ring)\, i. e. of the varieties of the form BwB/B\, where w is an element of the Weyl group. As a ring\, it is almost generated by the classes of Schubert varieties of codimension 1\, called Schubert divisors. More precisely\, the subring generated by Schubert divisors is a subgroup of finite index. These two facts lead to the following general question: how to decompose a product of Schubert divisors into a linear combination of Schubert varieties. In my talk\, I am going to address (and answer if I have time) two more particular versions of this question: If G is of type A\, D\, or E\, when does a coefficient in such a linear combination equal 0? When does it equal 1? \nIn the second part of my talk\, I will define canonical dimension of varieties (which\, roughly speaking\, measures how hard it is to get a rational point in a given variety) and canonical dimension of algebraic groups (which\, roughly speaking\, measures how complicated the torsors of an algebraic group can be). Then I will state a theorem about an upper estimate on the canonical dimension of the group and its torsors following from the fact that a certain coefficient we obtained in the first part of my talk (i. e. the coefficient in the decomposition of a product of Schubert divisors into a linear combination of Schubert varieties) equals 1. As a result\, we will get some explicit numerical estimates on canonical dimension of simply connected simple split algebraic groups of type A\, D\, and E.
URL:https://ccg.ibs.re.kr/event/2022-01-25-1620/
LOCATION:B266\, IBS\, Korea\, Republic of
CATEGORIES:Algebraic Geometry Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20220127T110000
DTEND;TZID=Asia/Seoul:20220127T120000
DTSTAMP:20260615T043905
CREATED:20220127T020000Z
LAST-MODIFIED:20220103T112105Z
UID:306-1643281200-1643284800@ccg.ibs.re.kr
SUMMARY:Jongbaek Song\, Regular Hessenberg Varieties and Toric Varieties
DESCRIPTION:     Speaker\n\n\nJongbaek Song\nKIAS\n\n\n\n\n\nA Hessenberg variety is a subvariety of the flag variety (G/B) determined by two parameters: one is an element of the Lie algebra of G and the other is a B-submodule containing the Lie algebra of B\, known as a Hessenberg space. In this talk\, we focus on elements in the regular locus of the Lie algebra and the Hessenberg space determined by negative simple roots. Then\, we aim to figure out cohomological relationship of these Hessenberg varieties with a certain class of toric varieties having orbifold singularities. The main result raises an interesting topic concerning toric varieties with symmetries by reflections. This is a joint work with M. Masuda\, T. Horiguchi and J. Shareshian.
URL:https://ccg.ibs.re.kr/event/2022-01-27/
LOCATION:TBA
CATEGORIES:Complex Geometry Seminar
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