Table of Contents

De Rham's Theorem

December 2023

De Rham's theorem provides an important connection between topology and smooth manifolds---that for manifolds, the de Rham cohomology is exactly the (real) singular cohomology, and the isomorphism is given by integration. Read more

Covering Spaces

August 2022

Covering spaces are a cool thing in topology. Finding covering spaces is like unwrapping a topological space. There are intimate connections between the fundamental group and covering spaces. Read more

Nullstellensatz

July 2022

Hilbert's Nullstellensatz is an important theorem in providing a bridge between algebra and geometry. This article walks through topics in commutative algebra before arriving at a proof of the theorem. Read more

Sylow Theorems

December 2021

The Sylow Theorems are fundamental to the study of finite groups. We build up to their proof by (1) studying group actions, (2) focusing on existence, and finally (3) studying conjugation of Sylow subgroups. Read more

Products and Coproducts

December 2021

We get our feet wet in category theory by going through the universal properties of products and coproducts. We'll see some examples and prove uniqueness of products. Then, we prove uniqueness of coproducts by duality. Read more