A while back, I made a YouTube video explaining how to self-study pure math:
To date, it’s the most viewed video on the channel.
Since then, I’ve received a lot of emails asking for more detailed learning resources. So in the next few issues, I wanted to collate this information and share it with you.
Here are the topics I’ll be covering in this guide:
Linear Algebra
Point Set Topology
Group Theory
Differential Geometry
Some general tips
But before we dive in, I wanted to share some general tips that helped me when learning math.
Learning math takes time. The subjects I’ll share today cannot really be studied in a few days’ time. Each subject would take 4 months to really study well.
Do as many problems as possible. So for each topic, I’ve included resources (most of which are freely / cheaply available) that include a lot of practice problems.
Re-read these books many times. I normally only really understand a textbook after having read it 4 times. Most people are the same.
If possible, find a friend to explain things to. I learn better by explaining things to people. I expect most people are the same!
Let’s get into it!
Linear Algebra
Book: Linear Algebra Done Right by Sheldon Axler – Focuses on vector spaces and linear transformations, offering a fresh perspective without relying heavily on determinants.
Videos: Sheldon Axler’s Playlist – A concise lecture series that complements the book’s content. Playlist here.
Point Set Topology
Online Notes: MAT327 Course Notes – Comprehensive notes with problems, ideal for building a strong foundation in topology. Available here.
Group Theory
Book: Topics in Algebra by I.N. Herstein (Chapter 2) – An accessible yet rigorous introduction to the foundations of group theory.
Videos: Lectures by Benedict Gross – Clear and engaging lectures that explore group theory concepts step by step. One of my favorite lecture series!
Differential Geometry
Book: Introduction to Differentiable Manifolds and Riemannian Geometry by Boothby. A thorough introduction to the concepts and tools of differential geometry, suitable for advanced learners.
Videos: Online Lectures by Fredrich Schuller. These were the lecture videos that first got me interested in math!
Challenge Problem
Here’s this week’s challenge problem:
The integers 1, ..., n are arranged in any order. In one step you may switch any two neighboring integers. Prove that you can never reach the initial order after an odd number of steps.
Got a solution to the challenge problem? Submit it here.
Solution from last week
See here for the solution to last week’s problem.
Huge thanks to Charles Burns (Oxford) and Chris (Italy) for submitting solutions to last week’s challenge problem.
Thanks for reading and happy learning! See you next week,
Adithya
Thoughts on Math Academy from Justin Skycak?
Recommending Axler almost makes me want to unsubscribe. I specifically anti-acknowledge it in my own notes! "With a dishonorable mention going to Sheldon Axler’s Linear Algebra Done Right, for putting determinants at the end for some ungodly reason."
Properly motivated, the determinant is an incredibly useful tool. I found this video helpful the last time I taught linear algebra https://youtu.be/Sv7VseMsOQc
I do agree that one should focus on vector spaces and linear transformations - the alternative is endless calculations with no appreciation of the broader theory.