BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Center for Complex Geometry - ECPv6.16.4.1//NONSGML v1.0//EN
CALSCALE:GREGORIAN
METHOD:PUBLISH
X-WR-CALNAME:Center for Complex Geometry
X-ORIGINAL-URL:https://ccg.ibs.re.kr
X-WR-CALDESC:Events for Center for Complex Geometry
REFRESH-INTERVAL;VALUE=DURATION:PT1H
X-Robots-Tag:noindex
X-PUBLISHED-TTL:PT1H
BEGIN:VTIMEZONE
TZID:Asia/Seoul
BEGIN:STANDARD
TZOFFSETFROM:+0900
TZOFFSETTO:+0900
TZNAME:KST
DTSTART:20250101T000000
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20260701T163000
DTEND;TZID=Asia/Seoul:20260701T173000
DTSTAMP:20260621T160131Z
CREATED:20260621T160131Z
LAST-MODIFIED:20260621T160131Z
UID:4601-1782923400-1782927000@ccg.ibs.re.kr
SUMMARY:Birational contractions of \(\overline{\mathrm{M}}_{g\,n}\) and their dependence on the characteristic
DESCRIPTION:    Speaker\n\n\nDaebeom Choi\nUniversity of Pennsylvania\n\n\n\n\n\n\nIn this talk\, we discuss the existence and nonexistence of certain birational contractions of \(\overline{\mathrm{M}}_{g\,n}\). Somewhat surprisingly\, this depends on the characteristic of the base field: many such contractions exist only in positive characteristic. We present a precise form of this phenomenon and discuss two examples that highlight the difference between characteristic zero and positive characteristic. The first is a simple and explicit contraction that exists only in positive characteristic\, and the second is a modular interpretation of the morphisms associated with psi classes on \(\overline{\mathrm{M}}_{1\,n}\). We also offer some speculation on why such characteristic-dependent phenomena arise.
URL:https://ccg.ibs.re.kr/event/birational-contractions-of-overlinemathrmm_gn-and-their-dependence-on-the-characteristic/
LOCATION:B236-1\, IBS\, Korea\, Republic of
CATEGORIES:Algebraic Geometry Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20260703T110000
DTEND;TZID=Asia/Seoul:20260703T120000
DTSTAMP:20260624T023057Z
CREATED:20260624T022730Z
LAST-MODIFIED:20260624T023057Z
UID:4608-1783076400-1783080000@ccg.ibs.re.kr
SUMMARY:Mutation of Fano Simplices and Markov type equations
DESCRIPTION:    Speaker\n\n\nYunhyung Cho\nSungkyunkwan University\n\n\n\n\n\n\nIt is well known that there is a bijective correspondence between the set of positive integer solutions to the Markov equation and the set of Fano triangles mutation equivalent to the Fano triangle of $\mathbb{P}^2$. \nIn this talk\, we establish a higher dimensional generalization of this correspondence for arbitrary Fano simplices of any dimension. On the polyhedral side\, we introduce a distinguished class of facets\, called admissible facets\, and show that their number is preserved under facet mutation. As a consequence\, facet mutation classes of Fano simplices carry natural exchange graph structures whose valency is equal to the number of admissible facets. On the arithmetic side\, we associate to each Fano simplex a weighted Markov-type equation together with a distinguished positive integer solution\, and show that the corresponding arithmetic mutations\, given by Vieta involutions\, are compatible with facet mutations. More precisely\, the assignment from Fano simplices to Diophantine data intertwines combinatorial mutations with arithmetic mutations\, thereby relating the mutation dynamics of Fano simplices to the arithmetic dynamics of positive integer solutions. Finally\, we introduce a piecewise linear transformation on dual polytopes\, called a sliding operator\, which realizes combinatorial mutation in the dual picture. As applications\, we obtain a volume formula for dual simplices in terms of the associated Diophantine data and recover the multiplicity change formula under mutation.
URL:https://ccg.ibs.re.kr/event/mutation-of-fano-simplices-and-markov-type-equations/
LOCATION:B236-1\, IBS\, Korea\, Republic of
CATEGORIES:Algebraic Geometry Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20260709T163000
DTEND;TZID=Asia/Seoul:20260709T173000
DTSTAMP:20260623T033832Z
CREATED:20260609T062941Z
LAST-MODIFIED:20260623T033832Z
UID:4571-1783614600-1783618200@ccg.ibs.re.kr
SUMMARY:Indeterminacy of period map for hypersurfaces
DESCRIPTION:    Speaker\n\n\nSung Gi Park\nPrinceton University\n\n\n\n\n\n\nI will discuss the indeterminacy locus of the period map from the moduli space of hypersurfaces to the period domain and its compactifications. In the case of quartic K3 surfaces\, the result verifies the expectation of Laza and O’Grady that the period map from the GIT compactification is regular precisely on the semi-log canonical locus.
URL:https://ccg.ibs.re.kr/event/tba-6/
LOCATION:B236-1\, IBS\, Korea\, Republic of
CATEGORIES:Algebraic Geometry Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=Asia/Seoul:20260710T100000
DTEND;TZID=Asia/Seoul:20260710T110000
DTSTAMP:20260621T155950Z
CREATED:20260609T063041Z
LAST-MODIFIED:20260621T155950Z
UID:4573-1783677600-1783681200@ccg.ibs.re.kr
SUMMARY:Hodge structure on the singular cohomology of singular cubic fourfolds
DESCRIPTION:    Speaker\n\n\nHyunsuk Kim\nUniversity of Michigan\n\n\n\n\n\n\nConsidering the singular cohomology of a cubic fourfold yields a morphism from the moduli space of (smooth) cubic fourfolds to the period domain. Both spaces have natural compactifications\, the GIT moduli space of cubic fourfolds parametrizing all GIT polystable objects\, and the Baily-Borel compactification of the period domain\, purely coming from group theory. This yields a birational map between two projective varieties. Laza and Looijenga independently gave a precise description of the birational geometry between these two spaces. Recently\, Sung Gi Park gave a systematic understanding on this picture using Hodge-Du Bois theory and higher singularities\, which have been developed by Friedman-Laza\, Mustata-Popa\, and many others. \nIn order to attack this question\, it is vital to understand the Hodge structure on the singular cohomology of a singular member in this moduli problem\, and also the Hodge theoretic properties of a degeneration to it. In a joint work with Kenny Ascher\, Jennifer Li\, Lisa Marquand\, Sung Gi Park\, and Sasha Viktorova\, we systematically carry out the calculation of the Hodge-Du Bois diamond of all GIT polystable cubic fourfolds using techniques coming from Saito’s Hodge modules.
URL:https://ccg.ibs.re.kr/event/tba-7/
LOCATION:B236-1\, IBS\, Korea\, Republic of
CATEGORIES:Algebraic Geometry Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;VALUE=DATE:20261109
DTEND;VALUE=DATE:20261114
DTSTAMP:20260613T170852Z
CREATED:20260307T152404Z
LAST-MODIFIED:20260613T170852Z
UID:4463-1794182400-1794614399@ccg.ibs.re.kr
SUMMARY:Conference on Complex Geometry
DESCRIPTION:Speakers\nRodolf Aguilar Aguilar (CIMAT\, Guanajuato)\nCong Ding (Shenzhen U.)\nCecil Gachet (U. Bochum)\nJaehyun Hong (IBS-CCG)\nXiaojun Huang (Rutgers U.)\nYuta Kusakabe (Kyushu U.)\nMinseong Kwon (AMSS\, Beijing)\nSuichung Ng (ECNU\, Shanghai)\nDan Popovici (U. Toulouse)\nVasily Rogov (MPI\, Leipzig)\nMin Ru (U. Houston)\nAeryeong Seo (Kyungpook National U.)\nLaurent Stolovitch (U. Nice)\nSheng-Li Tan (ECNU\, Shanghai)\nWing-Keung To (National U. Singapore)\nI-Hsun Tsai (National Taiwan U.)\nJulie Wang (Academia Sinica\, Taipei)\nKwok Kin Wong (Shenzhen U.) \nAbstracts\nTBA \nSchedule\nTBA \nOrganizers\nPhilippe Eyssidieux (U. Grenoble)\nJun-Muk Hwang (IBS-CCG)\nSung Yeon Kim (IBS-CCG)\nNgaiming Mok (U. Hong Kong) \nVenue\nScience Culture Center\, IBS\, Daejeon\, Korea \nMore Information\n• How to get to IBS-CCG
URL:https://ccg.ibs.re.kr/event/2026-11-09-13/
LOCATION:IBS Science Culture Center\, Daejeon\, Korea\, Republic of
CATEGORIES:Conferences and Workshops
END:VEVENT
END:VCALENDAR