“Wir müssen wissen — wir werden wissen.” — David Hilbert, Königsberg, 1930

A notebook for the ideas I want to understand properly, not just use.


What this is

The Hilbert Notebooks is a personal working journal — somewhere between a textbook chapter and a lab notebook. Each page picks one idea, takes it apart down to the mathematics that makes it work, then puts it back together in code.

Written for: Future me, who will inevitably forget all of this and need a clean reference.

If a page assumes prior knowledge, it says so up top. If a claim needs a proof, it gets one. No hand-waving.


About me

I’m Ashfak Hossain — a dumb with a stubborn belief that you don’t really understand an algorithm until you can re-derive it from scratch on a napkin.

I write here partly to teach, partly to learn, and partly to leave a paper trail I can follow back when I forget the details — which I always do.


Colophon

This site is built with Quartz (a fast static-site generator for digital gardens), authored in Obsidian, math rendered by KaTeX, syntax highlighting by Shiki, hosted on GitHub Pages. Source is open at github.com/Ashfak-Hossain/codex — fork it, copy from it, file issues, send corrections.

Typography: Proza Libre for headings, Bricolage Grotesque for body, IBM Plex Mono for code.


Get in touch

If you spot a mistake, a missing step in a proof, or a place where the prose is murky — please tell me. I would rather be corrected than be wrong in public.


The ideas don’t age.