<?xml version="1.0" encoding="utf-8" standalone="yes"?><rss version="2.0" xmlns:atom="http://www.w3.org/2005/Atom" xmlns:content="http://purl.org/rss/1.0/modules/content/"><channel><title>Higher Algebra on Ou Liu</title><link>https://ou-liu-red-sugar.github.io/tags/higher-algebra/</link><description>Recent content in Higher Algebra on Ou Liu</description><generator>Hugo -- 0.146.0</generator><language>en-us</language><lastBuildDate>Fri, 24 Apr 2026 00:00:00 +0000</lastBuildDate><atom:link href="https://ou-liu-red-sugar.github.io/tags/higher-algebra/index.xml" rel="self" type="application/rss+xml"/><item><title>Compactly assembled categories</title><link>https://ou-liu-red-sugar.github.io/notes/notes/continuous-k-theory/compactly-assembled-categories/</link><pubDate>Fri, 24 Apr 2026 00:00:00 +0000</pubDate><guid>https://ou-liu-red-sugar.github.io/notes/notes/continuous-k-theory/compactly-assembled-categories/</guid><description>Dualizable stable categories from the compactly assembled viewpoint: R-linear categories, dualizability in $\mathsf{Pr}_{\mathrm{st}}^L$, compactly exhaustible objects, the Lurie–Clausen characterisation, and the symmetric monoidal structure of $\mathsf{Pr}^L_{\mathrm{ca}}$.</description></item><item><title>Basic Concepts on Higher Algebra</title><link>https://ou-liu-red-sugar.github.io/notes/notes/basic-concepts-on-higher-algebra/</link><pubDate>Mon, 22 Sep 2025 00:00:00 +0000</pubDate><guid>https://ou-liu-red-sugar.github.io/notes/notes/basic-concepts-on-higher-algebra/</guid><description>This note introduces algebraic patterns and Segal objects, develops operads over algebraic patterns, and studies $\mathcal{O}$-monoidal categories together with $\mathcal{O}$-algebras in the Cartesian setting.</description></item><item><title>Sheaf Cohomology as Sheafification</title><link>https://ou-liu-red-sugar.github.io/notes/notes/sheaf-cohomology-as-sheafification/</link><pubDate>Sat, 27 Dec 2025 00:00:00 +0000</pubDate><guid>https://ou-liu-red-sugar.github.io/notes/notes/sheaf-cohomology-as-sheafification/</guid><description>Sheaf cohomology is evaluation of the sheafification: \(\Gamma(X, \mathcal{F}) \coloneqq (L\mathcal{F})(X)\). Reading Mayer–Vietoris, derived Čech, pushforward, base change and the vanishing \(H^i(\mathrm{Spec}\,R, \widetilde{M}) = 0\) directly off the sheaf condition, without spectral sequences or injective resolutions.</description></item><item><title>Stable Dold–Kan and Descent</title><link>https://ou-liu-red-sugar.github.io/notes/notes/stable-doldkan-and-descent/</link><pubDate>Thu, 27 Nov 2025 00:00:00 +0000</pubDate><guid>https://ou-liu-red-sugar.github.io/notes/notes/stable-doldkan-and-descent/</guid><description>Unified exposition of the stable Dold–Kan correspondence and its application to descent theory in stable categories.</description></item></channel></rss>