Sorry if this is a dumb request but im taking a gap semester, and I want to torture myself. After im done with whatever I have planned for the day, I want to spend a couple hours doing math. I want the most rigorous graduate level or research level piece of mathematics I can read. I want it extremely dense. Need some recommendations. This might be a bad analogy but in computer science terms I’d like to “code” in c++ and not assembly so like not boring first order set theory but category theory etc. I don’t care about ROI here, just pure torture, actually negative ROI is preferred here. As of now the most difficult piece of mathematics I’ve encountered are some results from the Kudla program, and was wondering if there’s anything more difficult/dense to grasp or understand in its entirety.