November 6, 2025
High math, low raccoon
The Geometry of Schemes [pdf]
Deep math book drops, but everyone’s obsessed with a raccoon
TLDR: A serious algebraic geometry textbook PDF is making waves, but the community is split between debates on accessibility (“should biologists learn this?”) and memes about a mysterious raccoon image. The drama matters because it spotlights how math communication collides with culture, attention, and who scholarly work is really for.
The heavyweight math tome “The Geometry of Schemes” by David Eisenbud and Joe Harris is trending—not for its brain-bending chapters on shapes, spaces, and how numbers glue together, but because the comments turned it into a soap opera. One camp’s hot take, led by gsf_emergency_4’s blunt “Teach biologists that?”—paired with a Grothendieck think-piece—sparked a full-on debate: should non-math folks be dragged into grad-level geometry, or is this gatekeeping disguised as outreach? The purists champion the book’s rigor (think: careful definitions, “local rings,” and projects about “tangent cones”), while accessibility warriors argue this reads like a boss fight without a tutorial.
Then the raccoon happened. Pixelpoet’s “What’s up with the raccoon on page 67?” detonated meme mode. SherryMarcini declared the critter “ruined” the vibe, and the thread split: mathematicians begging for focus vs. jokesters dubbing it the “Spec Coon,” inventing a “sheaf of snacks,” and claiming “flat families” are pancakes. The result: high-brow algebraic geometry collides with low-key chaos. Whether you’re here for projective space or just raccoon lore, the community made this scholarly PDF feel like reality TV—with equations.
Key Points
- •The text systematically introduces schemes, starting from affine schemes and building via topology and structure sheaves, supported by an interlude on sheaf theory.
- •General tools include subschemes, local rings, morphisms, and gluing, with extensions to relative schemes (fibered products, S-schemes, global Spec) and the functor of points.
- •A broad range of examples covers reduced and nonreduced schemes, including double/multiple points, embedded points, degrees, multiplicities, and primary decomposition.
- •Arithmetic schemes are treated through concrete constructions over Spec Z, such as affine spaces, conics, and double points in A1_Z.
- •Projective schemes are developed via Proj of graded rings and sheaves, projectivization, tangent spaces/cones, morphisms to projective space, Grassmannians, universal hypersurfaces, and invariants like Hilbert polynomials and flatness in families.