I am Yeonsol Kim, an undergraduate in mathematics based in Korea. I began my BSc in Mathematics in 2026.
This site, External, is where I keep my notes as I learn. Most of them are on mathematics; the rest are on physics, economics, English and other subjects.
These are study notes, not original research. A note that follows a textbook or another work lists it under References at the end. They are written while I am still learning the material, so they may contain mistakes; corrections are very welcome (see Contact).
Audio narration
Many notes can also be listened to, on the page or as a podcast. The narration is generated with OpenAI models: a language model turns the note into a spoken script, and a text-to-speech model reads it aloud. The voice is AI-generated, not a human voice. Where the audio and the text differ, the text is authoritative.