---
date: 2022-01-16
tags: [ web/quick-notes ]
---

# 2022-01-16

Tags:
#web/quick-notes

Refs:
?

## 22:03

The disc and the sphere, defined in chain complexes, along with some other nice constructions:


![](figures/2022-01-16_22-04-10.png)

Thick subcategories:


![](figures/2022-01-16_22-05-30.png)