RUS  ENG JOURNALS   PEOPLE   ORGANISATIONS   CONFERENCES   SEMINARS   VIDEO LIBRARY   PACKAGE AMSBIB
Forthcoming seminars
Seminar calendar
List of seminars
Archive by years
Register a seminar

Search
RSS
Forthcoming seminars





You may need the following programs to see the files








Iskovskikh Seminar
September 30, 2020 15:00, Moscow, online
 


Surface fibrations with large equivariant automorphism groups

Yi Gu

Number of views:
This page:84

Yi Gu
Photo Gallery

Abstract: Given a fibration $f: X\to C$ from a smooth projective surface $X$ to a smooth curve $C$ over an arbitrary algebraically closed field $k$. The equivariant automorphism group is
$$\mathbb{E}(X/C):=\{  (\tau,\sigma)   |   \tau\in \mathrm{Aut}_k(X), \sigma\in \mathrm{Aut}_k(C),    f\circ \tau =\sigma\circ f   \}$$
with natural composition law.
$$ \xymatrix{ X\ar[rr]_\sim^\tau \ar[d]_f&& X \ar[d]^fC \ar[rr]_\sim^\sigma && C } $$
This group is an important invariant of the fibration $f$ and sometimes that of the surface $X$. In this talk, we will give a classification of those relatively minimal surface fibrations whose equivariant automorphism group $\mathbb{E}(X/C)$ is infinite. As an application, we will also discuss the Jordan property of the automorphism group of a minimal surface of Kodaira dimension one.

Language: English

SHARE: VKontakte.ru FaceBook Twitter Mail.ru Livejournal Memori.ru
 
Contact us:
 Terms of Use  Registration  Logotypes © Steklov Mathematical Institute RAS, 2020