Algebraic Geometry Seminar

Seminar information archive ~02/02Next seminarFuture seminars 02/03~

Date, time & place Friday 13:30 - 15:00 118Room #118 (Graduate School of Math. Sci. Bldg.)
Organizer(s) GONGYO Yoshinori, KAWAKAMI Tatsuro, ENOKIZONO Makoto

2025/10/31

15:00-16:30   Room #118 (Graduate School of Math. Sci. Bldg.)
Masafumi Hattori (University of Nottingham)
Normal stable degeneration of Noether-Horikawa surfaces: Deformation Part
[ Abstract ]
Koll’ar and Shepherd-Barron constructed a general theory for a canonical geometric compactification of moduli of smooth surfaces with ample canonical class by adding degenerations with only semi log canonical singularities. Their moduli is now called the KSBA moduli and degenerations are called stable degenerations. It has been a long standing question to classify all stable degenerations for smooth canonically polarized surfaces. In this talk, we focus on Q-Gorenstein deformation theory on Horikawa surfaces, which are minimal surfaces of general type in the case where the Noether inequality $K^2\geq 2p_g-4$ is an equality. This talk is based on the joint work (arXiv:2507:17633) with Hiroto Akaike, Makoto Enokizono, and Yuki Koto.