This site shares my book on differential geometry and its use for understanding latent factors in machine learning.
I have been using the book for some years as an internal reference for my group. In recent years, I have also been using the book as lecture notes for parts of an advanced machine learning course. It is written with an emphasis on being accessible as existing material can be difficult to get into without a background in mathematics.
In case you wonder why the site is called "Weekend with Bernie", then it is because the material is trying to be easily accessible (hence "weekend") and it leans on work by Bernhard Riemann (hence "Bernie"). The title may also be a reference to a fantastic movie...
Feel free to get in contact with me in case you have thoughts on the topic.