Title：Elliptic fibrations on K3 surfaces and Salem numbers of maximal degree

Speaker：Xun Yu （Tianjing University）

Time：2018年4月13日（周五）    上午 10:00-11:30

Room：东区管理科研楼  0029cc金沙贵宾会1208室

Abstract：We explain a characterization of the maximal Salem degree of automorphisms of K3 surfaces in terms of elliptic fibrations with infinite automorphism groups. As an application, we show that any supersingular K3 surface in odd characteristic has an automorphism the entropy of which is the natural logarithm of a Salem number of degree 22. In particular, such automorphisms are not geometrically liftable to characteristic 0.