Contents:

Sept 25, 2014 – Lectures 1 and 2

Introduction. Definition of (affine) algebraic set.

Examples: skew cubic curve, GL(n,K) as algebraic sets.

([1] Chapter 0, examples 0.5-0.7, 0.13-0.15)

Maps V and I and their properties. Examples.

([1] Chapter 1, §1.1 and [3] ex.1.6)

Sept 29, 2014 – Lectures 3 and 4

Radical ideals. Hilbert’s Nullstellensatz.

Definition of Zariski topology.

Irreducible algebraic sets and prime ideals. Definition of affine variety.

The skew cubic curve is irreducible.

([1] Chapter 1, §1.1)

Oct 2, 2014 – Lectures 5 and 6

Example of reducible algebraic set.

Decomposition of an algebraic set in irreducible components.

([1] Chapter 1, §1.1, [2] §3.11-worked examples)

Properties of the Zariski topology . Product of algebraic sets. Topology of the products.

Topological dimension of an algebraic set.

([1] Chapter 1, §1.1 and [4] Chapter 1, §1)

Oct 6, 2014 – Lectures 7 and 8

Polynomial functions and maps: coordinate ring of an affine variety. Examples

([1] Chapter 1, §1.2.1)

Rational functions and quotient field of K[V].

([1] Chapter 1, §1.3)

Polynomial maps and k-algebra homomorphisms. Examples

([1] Chapter 1, §1.2.2)

Functor between the category of affine varieties and of f.g., reduced, k-algebras.

([1] Chapter 1, §1.2.3).

Oct 9, 2014 – Lectures 9 and 10

Rational maps. Dominant rational maps and homorphisms between function fields. Examples.

([1] Chapter 1, §1.3.3)

Birational maps. ([1] Chapter 1, §1.3.4) and isomorphism between function fields.

Oct 13, 2014 – Lectures 11 and 12

Examples of rational affine varieties: cubic curve with a cusp, quadric surface and

cubic surface with two skew lines.

([5] §3.3, examples 1 and 2)

Isomorphism between a principal open set and an affine variety.

([1] Chapter 1, §1.3.4)

Projective spaces, duality, and projective sets.

([1] Chapter 2, §2.1 and 2.2

Oct 16, 2014 – Lectures 13 and 14

Examples of projective varieties: the rational normal cubic.

([6] Lecture 1)

The variety of the chords to the rational normal cubic.

([6] Lecture 1)

The Segre embedding of P1 xP1.

([6] Lecture 2)

P5 parameterizing the conics of P2: the cubic hypersurface of singular conics

and lines corresponding to pencils of conics. The Veronese surface.

([6] Lecture 4, example 4.8)

Oct 20, 2014 – Lectures 15 and 16

Properties of Veronese surface.

([6] Lecture 4, example 4.8)

Spaces parameterizing hyperquadrics and Veronese maps.

Graduate rings and homogeneous ideals.

([1] Chapter 2, §2.1 and 2.2)

Oct 23, 2014 – Lectures 17 and 18

Affine cones. Projective Hilbert’s Nullstellensatz. Projective algebraic varieties.

Zariski topology on Pn.

([1] Chapter 2, §2.1 and 2.2)

Rational functions on projective varieties and morphisms

([1] Chapter 2, §2.3).

Oct 27, 2014 – Lecture 19 and 20

Rational functions on projective varieties and morphisms

([1] Chapter 2, §2.3)

Rational and birational maps. Examples.

([1] Chapter 2, §2.3, [5] Chapter 1, §4.4)

Oct 30, 2014 – Lecture 21 and 22

Product of projective varieties and Segre embedding. Projection maps.

([5] Chapter 1, §5.1)

Subvarieties of the Segre varieties.

([5] Chapter 1, §5.2)

Segre products as categorical products.

([6] Chapter 2)

Nov 3, 2014 – Lecture 23 and 24

Graph of a regular map.

Image of a projective variety under regular maps.

([5] Chapter 1, §5.2)

Introduction to Blow-up of A^2 in the origin.

Nov 6, 2014 – Lecture 25 and 26

Blows-up.

([1] Chapter 2, §2.3.6)

Examples: resolution of singularities of plane curves, quadratic transformations

and blow-up of a quadric in one point.

([1] Chapter 2, §2.3.6, [4] Chapter 5, example 4.2.3)

Rational and Unirational projective varieties.

([6] Lecture 7)

Nov 10, 2014 – Lecture 27 and 28

Finite maps between affine varieties and their properties (with finite fibers,

surjective, closed). Examples.

Finite maps between projective varieties.

([5] Chapter 1, §5.3)

Projections are finite morphisms.

Nov 13, 2014 – Lecture 29 and 30

Noether Normalization Lemma and geometric consequences.

([5] Chapter 1, §5.4)

Smooth points and tangent spaces to hypersurfaces and to affine varieties.

([1] Chapter 3, §3.1)

Nov 17, 2014 – Lecture 31 and 32

Smooth points and tangent spaces to hypersurfaces and to affine varieties.

Dimension of a variety through tangent spaces.

([1] Chapter 3, §3.1)

Algebraic Characterization of the dimension of a variety and behavior of

dimension under birational maps.

([1] Chapter 3, §3.2)

Dimension of the intersection of a projective variety with a hypersurface.

([5] Chapter 1, §6.2, §6.3)

Nov 20, 2014 – Lecture 33 and 34

Dimension of the intersection of projective varieties.

([5] Chapter 1, §6.2, §6.3)

Geometric definition of dimension of a projective variety

([6] Lecture 11)

Geometric definition of degree of a projective variety and Weak Bezout Theorem.

([6] Lecture 7)

Nov 24, 2014 – Lecture 35 and 36

Algebraic Preliminaries to Hilbert Polynomial: primary decomposition of an

homogeneous ideal and examples.

Definition of the Hilbert function of an homogeneous

ideal and of a projective set. Examples: Hilbert function of a set of points.

Properties of the Hilbert function.

([8] chapters 2,3)

Nov 27, 2014 – Lecture 37 and 38

Hilbert polynomial and dimension and degree of a projective variety.

([8] chapters 2,3)

Introduction to Grassmmann varieties.

Definition of G(1,3).([7])

Dec 1, 2014 – Lecture 39 and 40

Subvarieties of G(1,3): linear complexes.

Rationality of the quadratic complex.

Definition of G(k,n).

Examples of enumerative geometry ([7])

Dec 4, 2014 – Lecture 41 and 42

Dimension of fibres of a regular map.

([5] Chapter 1, §6.2, §6.3)

Lines on a generic surface of P^3.

([5] Chapter 1 - §6.4)

References:

[1] K.Hulek – Elementary Algebraic Geometry – AMS

[2] M.Reid – Undergraduate Algebraic Geometry – London Mathematical Society Student Texts 12

[3] K.Ueno – Algebraic Geometry 1 – From Algebraic Varieties to Schemes – Translations of Mathematical Monographs – AMS Vol. 185.

[4] R. Hartshorne Algebraic geometry Graduate Texts in Math. No. 52. Springer-Verlag, New York-Heidelberg, 1977.

[5] I. Shafarevich Basic algebraic geometry vol. 1 Springer-Verlag, New York-Heidelberg, 1977.

[6] J. Harris Algebraic geometry (a first course) Graduate Texts in Math. No. 133. Springer-Verlag, New York-Heidelberg, 1977.

[7] S. L. Kleiman and Dan Laksov Schubert Calculus The American Mathematical Monthly, Vol. 79, No. 10 (Dec., 1972), pp. 1061-1082

[8] E. Arrondo – Introduction to projective varieties – Lecture notes of Phd courses.