• Yoonjoo Kim, Two results on Lagrangian fibrations

    B236-1 IBS, Korea, Republic of
    Algebraic Geometry Seminar

        Speaker Yoonjoo Kim Columbia U. I would like to report two ongoing results on Lagrangian fibrations of smooth symplectic varieties. The first is the construction of a delta-regular smooth group scheme that acts on a given Lagrangian fibration. It is a generalization of the result of Arinkin-Fedorov, who proved the result under the

  • Hyukmoon Choi, Equivariant compactification structures on smooth projective horospherical varieties of Picard number 1

    B236-1 IBS, Korea, Republic of
    Complex Geometry Seminar

        Speaker Hyukmoon Choi IBS CCG and KAIST A projective variety V is an equivariant compactification of an algebraic group G if there exists an algebraic G-action on V with a Zariski open orbit O, which is equivariantly biregular to G. Such a G-action is called an equivariant compactification (EC) structure on V. For

  • Makoto Enokizono, Normal stable degenerations of Noether-Horikawa surfaces

    B236-1 IBS, Korea, Republic of
    Algebraic Geometry Seminar

        Speaker Makoto Enokizono University of Tokyo Noether-Horikawa surfaces are surfaces of general type satisfying the equation K2=2pg−4, which represents the equality of the Noether inequality K2≥2pg−4 for surfaces of general type. In the 1970s, Horikawa conducted a detailed study of smooth Noether-Horikawa surfaces, providing a classification of these surfaces and describing their moduli spaces.

  • Doyoung Choi, Singularities and syzygies of secant varieties of smooth projective varieties

    B236-1 IBS, Korea, Republic of
    Algebraic Geometry Seminar

        Speaker Doyoung Choi KAIST / IBS We study the higher secant varieties of a smooth projective variety embedded in projective space. We prove that when the variety is a surface and the embedding line bundle is sufficiently positive, these varieties are normal with Du Bois singularities and the syzygies of their defining ideals

  • Haesong Seo, Algebraic hyperbolicity of adjoint linear systems on spherical varieties

    B236-1 IBS, Korea, Republic of
    Algebraic Geometry Seminar

        Speaker Haesong Seo KAIST / IBS A projective manifold is called hyperbolic if it does not admit an entire map from the complex plane. Demailly proved that hyperbolic manifolds are algebraically hyperbolic, meaning that there are degree bounds for curves in terms of their genera. It is a highly challenging problem to determine

  • Qifeng Li, Minimal rational curves on equivariant compactifications of symmetric spaces

    B236-1 IBS, Korea, Republic of
    Complex Geometry Seminar

        Speaker Qifeng Li Shandong University Let X be a smooth equivariant compactification of a symmetric space. In this talk, we will discuss when a minimal rational curve on X is the orbit closure of a 1-parameter group. In case the symmetric space is of group type, the answer is positive and moreover the

  • Yong Hu, Moduli spaces of threefolds on the Noether line

    B236-1 IBS, Korea, Republic of
    Complex Geometry Seminar

        Speaker Yong Hu Shanghai Jiao Tong University In this talk, we will introduce the 3-dimensional Noether inequality and completely classify the canonical threefolds on the Noether line with $p_g \ge 5$ by studying their moduli spaces. For every such moduli space, we establish an explicit stratification, estimate the number of its irreducible components

  • Minseong Kwon, Automorphism groups of toroidal horospherical varieties

    B236-1 IBS, Korea, Republic of
    Algebraic Geometry Seminar

        Speaker Minseong Kwon Gyeongsang National University In the 1970s, Demazure studied the automorphism groups of two types of almost homogeneous varieties: rational homogeneous spaces and toric varieties. Especially, for a smooth complete toric variety, Demazure obtained a structure theorem for the connected automorphism group in terms of the so-called Demazure roots. In this

  • Moduli of Surfaces and Beyond

    IBS Science Culture Center Daejeon, Korea, Republic of
    Conferences and Workshops

      Speakers Lecture Series (3hr) Radu Laza (Stony Brook University) Matthias Schütt (Leibniz Universität Hannover) Jenia Tevelev (University of Massachusetts Amherst) Research Talks (1hr) Kenneth Ascher (University of California, Irvine) Dori Bejleri (University of Maryland, College Park) Harold Blum (Georgia Institute of Technology) Nathan Chen (Harvard University) Changho Han (Korea University) Donggun Lee (IBS-CCG) Samouil

  • Cauchy-Riemann Symmetry and Real Hypersurfaces in Hermitian Symmetric Spaces

    B236-1 IBS, Korea, Republic of
    Several Complex Variables Seminar

        Speaker Jong Taek Cho Chonnam National University We survey recent developments of pseudo-Hermitian geometry or CR geometry of hypersurface type, with a particular focus on their symmetries and realizations as real hypersurfaces in Hermitian symmetric spaces.

  • Perspectives in algebraic geometry

    B109 IBS, Korea, Republic of
    Conferences and Workshops

    The talks will begin on December 16, following a day of free discussion on December 15. Confirmed Speakers Lorenzo Barban (IBS-CCG) Junho Choe (KIAS) Karl Christ (University of Turin) Fei Hu (Nanjing University) Sukmoon Huh (Sungkyunkwan University) Jaehyun Kim (Ewha Womans University) Jeong-Seop Kim (KIAS) Shin-Young Kim (Kangwon National University) Haidong Liu (Sun Yat-sen University)

  • Enriques surfaces of zero entropy

    B236-1 IBS, Korea, Republic of
    Algebraic Geometry Seminar

        Speaker Gebhard Martin University of Bonn The automorphism group of a general Enriques surface is the 2-congruence subgroup of the Weyl group of the E10-lattice. In particular, it is infinite and not virtually solvable. On the other end of the spectrum, there do exist Enriques surfaces with finite automorphism group, first classified over