Math 8253: Class Outlines

Math 8253: Class Outlines, Fall 2022

o 12/14: Homework due by the beginning of class. Sheaves of modules. [[G]: Chapter 13 through 13.13, skipping 13.10 (b), 13.11, and 13.12]

o 12/09: Open and closed subschemes. Fiber products. Separated, reduced, finite-type schemes. Varieties and pre-varieties as schemes. [[G]: The rest of Chapter 12]

o 12/07: Locally ringed spaces and their morphisms, schemes. [[G]: Chapter 12 through 12.31, skipping 12.29]

o 12/02: Affine schemes, stalks and values of regular functions. Examples. [[G]: Chapter 12 through 12.21.]

o 11/30: Schemes, finally, on popular demand: the definition/construction of Spec R. [Lecture slides; [G]: Chapter 12 through 12.17]

o 11/23: Homework due by the beginning of class. The tangent and cotangent spaces and smooth varieties. [[G]: Chapter 10 through the end.]

o 11/18: Blowing up as extension of morphisms. The tangent space. [[G]: Section 9.26 and Chapter 10 through 10.1]

o 11/16: Blowing up as resolution of singularities. [[G]: Chapter 9 (Section 9.17(b) through 9.21, skipping tangent cones)]

o 11/11: Blowing up: the proper (strict) transform; equations defining the blowup; blowing up a point in 𝔸n. [[G]: Chapter 9 (Section 9.11 through 9.17(a))]

o 11/9: Intro to birational geometry. Rational and birational maps. The function field. Blowing up. [[G]: Chapter 9 through Section 9.11]

o 11/4: Grassmannians as projective varieties. [[G]: Chapter 8 from 8.14 through the end]

o 11/2: Homework due at the beginning of class. Exterior algebra. Grassmannians and the Plücker embedding. [[G]: Chapter 8 through 8.13]

o 10/28: Projective varieties: closed maps; complete varieties; the Veronese embedding. [[G]: Chapter 7 from Section 7.16 through the end]

o 10/26: Projective varieties: the Segre embedding; projective varieties are varieties; closed maps; complete varieties; the Veronese embedding. [[G]: Sections 7.9 through 7.15]

o 10/21: Projective varieties: morphisms; examples (PGL(n+1) = Aut ℙn, projections from a point; conics in ℙ2). [[G]: Chapter 7 through Section 7.8]

o 10/19: Homework due at the beginning of class. Projective varieties: properties of ℙn as a topological space; homogenization and projective closure; regular functions; projective varieties are prevarieties. [[G]: Chapter 6: 6.25 through the end; Chapter 7 through 7.3]

o 10/14: Projective varieties: affine cones, the homogenous coordinate ring, projective Nullstellensatz, projective subvarieties, the Zariski topology. [[G]: Chapter 6 from Section 6.12 through 6.24]

o 10/12: Projective space: intro. Graded algebra. Homogeneous ideals and projective varieties. [[G]: Chapter 6 through Section 6.12]

o 10/7: Prevarieties: gluing, examples, open and closed subprevarieties, products. Separation and varieties. [[G]: Chapter 5 from Section 5.4 to the end]

o 10/5: Homework due at the beginning of class. New viepoint on affine varieties. A distinguished open set is an affine variety. Prevarieties: intro. [[G]: Chapter 4 through the end; Chaptaer 5 through Section 5.3]

o 9/30: Morphisms. [[G]: Chapter 4 through 4.14]

o 9/28: The stalk 𝒪X,a is a localization. Ringed spaces. [[G]: Chapter 3 through the end; Chapter 4 through Section 4.1]

o 9/23: Homework due date revised to this class meeting. The affine plane with deleted origin is not a distinguished open set. Sheaves, including those of regular functions. The stalk and germs. Correction: no evaluation map ℱa → k, only 𝒪X,a → k. [[G]: Chapter 3 from 3.11 through 3.17]

o 9/21: Homework due at the beginning of class. Regular functions. Distinguished open sets. Regular functions over them. [[G]: Chapter 3 through 3.10]

o 9/16: Independent reading: the Zariski topology. Do related homework problems as you read! [[G]: Chapter 2 (through the end)]

o 9/14: Independent reading: subvarieties of an affine variety; the Zariski topology. Do related homework problems as you read! [[G]: Chapters 1 (through the end) and 2 (through 2.24)]

o 9/9: Proof of the easier parts of Nullstellenstaz. Bijection between affine varieties and radical ideals. Examples. Bijection between points and maximal ideals. Properties of the ideals of affine varieties. The coordinate ring. The idea of Zariski topology. [Class notes. [G]: Chapters 1 (through 1.15) and 2 (first page)]

o 9/7: Introduction. Affine algebraic varieties, a.k.a. affine algebraic sets: the loci V(S) of zeroes of a collection S of polynomials. Their properties. The ideal I(X) of a subset X of an affine space. First properties. Hilbert's Basis theorem and Nullstellensatz worded. [Syllabus. Class notes. [Gathmann]: Chapters 0 and 1 (through 1.10, not yet discussing the proof)]


Last modified: (2022-12-14 15:57:12 CST)