本文是作者今年的第四期月度笔记，记录了他在业余时间探索的三个主题。首先是学习Tutte著名定理证明的过程——该定理指出任意s-弧传递的有限三次图必须满足s ≤ 5。作者仔细研读了Norman Biggs《代数图论》中的证明，并写下约18页的详细笔记。其次，他回顾了群论中关于陪集的一些基础结论，并给出了简洁的证明。此外，文章还介绍了作者个人项目Wander Console的最新进展——这是一个去中心化的自托管网页控制台，用于推荐有趣的个人网站，目前网络中已有超过50个控制台，推荐了1400多个网页。
A Science paper and several other publications have incorrectly cited the compound Cr2Gr2Te6, which does not exist. The correct compound is Cr2Ge2Te6 (chromium germanium telluride), with Ge representing germanium. This typographical error has been copied across multiple scientific papers and a book chapter.
Evelyn Wood Reading Dynamics, launched in the 1950s, popularized speed reading despite scientific evidence questioning its claims of high-speed reading with full comprehension. The movement gained credibility through presidential endorsements but research shows it's essentially skimming with poor retention.
Dry ice (solid carbon dioxide) was commercialized in 1925 and became important for refrigerated transportation, reducing shipping costs by 50%. Northeastern New Mexico's Bueyeros field became a major source of pure CO2 for dry ice production. Today, much of the extracted CO2 is used for enhanced oil recovery, creating complex climate implications.