Vector Bundles, Locally Free Sheaves and Divisors on a Curve

In this post, I'll be summarizing the basics of the correspondence between vector bundles, locally free sheaves and divisors on a smooth curve (defined over an algebraically closed field $latex k$ of characteristic zero) together with some of their individual properties. Locally free sheaves and Vector bundles: Proposition 1: a) A coherent sheaf $latex \mathcal{E}$ on a … Continue reading Vector Bundles, Locally Free Sheaves and Divisors on a Curve

Classification of Vector Bundles on Elliptic curves

I'm supposed to give a talk on this subject for one of my courses, so I consider this post as a "pre-exposition." I learned from and heavily used the great exposition "Vector bundles on curves" by Montserrat Teixidor I Bigas in this post. I wrote up the pre-requisites here. In 1957, Atiyah in this famous paper "Vector bundles over … Continue reading Classification of Vector Bundles on Elliptic curves

Some Homological Algebra Computations

In this post, I'm going to write down the detailed proofs of some of the exercises in Rotman's Homological Algebra. They were asked in ML and then answered by me. 1. Let $latex A$ be a torsion abelian group. Then $latex \text{Ext}^1_\mathbb{Z}(A, \mathbb{Z}) \cong \text{Hom}_\mathbb{Z}(A,S^1)$, where $latex S^1$ is the unit circle. One point is … Continue reading Some Homological Algebra Computations