Algebraic geometry II - schemes and sheaves
MATH-510
Lecture 19 (20.11.24) summary
This page is part of the content downloaded from Lecture 19 (20.11.24) summary on Wednesday, 25 December 2024, 18:23. Note that some content and any files larger than 50 MB are not downloaded.
Page content
In this lecture, we covered the following topics:
-corrected the setup for Weil divisors, to include the assumption that the scheme is regular in codimension 1;
-definition of sheaf associated to a Weil divisor;
-motivation for Cartier divisor stemming from transition functions of vector bundles on manifolds;
-definition of Cartier divisor and local representability by the class of a rational function;
-homomorphism from Cartier divisors to Weil divisors and conditions for it to be injective;
-Cartier divisors correspond to locally principal Cartier divisors;
-example of a line through the vertex in the round cone;
-Weil divisors coincide with Cartier divisors if the underlying scheme is locally factorial (no proof).