Friday February 09, 2018 2:30 PM  3:30 PM Math Tower 5127
 Ben Wu, Stony Brook University
Pluricanonical forms and Gorenstein varietiesFor a smooth variety, the canonical bundle is defined to be the line bundle which is the determinant of the cotangent bundle. A canonical divisor is a divisor whose associated line bundle is the canonical bundle. For normal varieties, we still have a notion of canonical divisor despite the presence of singularities. However, the sheaf associated to this canonical divisor may fail to be locally free, i.e. is not a line bundle. When the sheaf associated to some multiple of the canonical divisor on a normal variety is locally free, the variety is called QGorenstein. In this talk, we will discuss how to define the canonical divisor on normal varieties and its associated sheaf and will discuss examples and nonexamples of QGorenstein varieties.
