Hi, my name is Chai and I’m taking an undergraduate quantum mechanics course at UCLA.

It’s known as one of the hardest classes at UCLA.

This text is written so that, at the start, you only need to know how to do basic middle school arithmetic.

In the end, you’ll know how to do quantum mechanics problems.

This text is loosely sorted by complexity. Everything is derived from concepts introduced in previous sections. As we introduce mathematical concepts, we will use them to better understand quantum mechanics.

This is based on the Electrical and Computer Engineering 128 course taught at the University of California, Los Angeles by Dr. Leo Zhou in 2026. This in turn based on Quantum Processes Systems and Information by Benjamin Schumacher and Michael Westmoreland written 2010.

Let us begin.

License: CC0 No rights reserved

None of this is written by AI

None of this is written by AI — I am writing this by hand because I find explaining concepts makes me understand them better too.

Everything must be defined above

Any mathematical term MUST be derived from first principles (or like elementary school math) in a section before it.

Example

invariant subspace → subspace → subset → Set

Contact

Please let me know at chaimongkol@ucla.edu on how I’m doing or that you’ve even read this message. If I see support, it makes me want to continue this series! The series is currently incomplete.