Curves and Surfaces

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Curves

Definitions

  • What is an algebraic curve?
  • What is the genus of a curve?
  • Special types of varieties:
    • What is a Fano variety?
    • What is a del Pezzo surface?
    • What is a ruled variety?
    • What is a uniruled variety?
    • What is an elliptic curve?
    • What is a hyperelliptic curve?
    • What is an abelian variety?
    • What is the Jacobian of a curve?
    • What is the Jacobian variety?
    • What is a Brill-Noether curve?
    • What is a Severi-Brauer variety?
  • What is the special divisor?
  • What is the ramification divisor?
  • What is the Frobenius map?
  • What is the j invariant?
  • What is an elliptic function?
  • What is the Hasse invariant?
  • What is the canonical embedding?
  • What is the anticanonical embedding?
    • The geometric genus?
    • The arithmetic genus?
    • The gonality?
    • The degree of a morphism \(C\to {\mathbb{P}}^r\)?
  • What is the dual curve?
  • What is the resultant?
  • What is the Kodaira dimension?
  • What is the Todd genus?
  • What is a minimal model of a smooth projective variety?
  • What is an elliptic fibration?
  • Types of surfaces:
    • An Enriques surface?
    • A K3 surface?
    • An elliptic surface?
    • A hyperelliptic surface?
    • An abelian surface?
    • What is the Hirzebruch surface?
      • Examples: attachments/Pasted%20image%2020220325225204.png
  • What is a log resolution?
  • What is a rational curve?
  • What is a stable map?
  • What is a reducible curve?
  • What is devissage?
  • What is a crepant map?
  • What is a complete intersection?
  • What are ADE singularities?
  • What is the Fermat quartic?

Results

  • What is Castelnuovo’s theorem?
  • What is the Riemann-Roch theorem for curves?
  • What is the Riemann-Hurwitz theorem for curves?
    • \(2-2 g_{1}=2\left(2-2 g_{0}\right)-\displaystyle\sum_{s \in X^{\mathrm{ram}}}\left(e_{s}-1\right)\)
  • What is Hurwitz’s theorem?
  • What is the classification of curves in \({\mathbb{P}}^3\)?
  • What is the Riemann-Hurwitz formula?
  • What is the genus formula for plane curves?
  • What is the Brill-Noether theorem?
  • Why is every genus 2 curve hyperellptic? Why is this not even generically true for \(g\geq 3\)?
  • How can you view a curve as a ramified cover of ${\mathbb{P}}^1_{/ {k}} $?
  • What is the cohomological criterion for ampleness?
  • Why is Zariski’s theorem true?
  • What is the Hodge index theorem?
  • What is Mori’s theorem?
  • What is Zariski’s main theorem?
  • What is the minimal model program for surfaces?

Problems

  • Show that if \(C\) is a smooth proper curve of genus \(g(C)\geq 2\), then \({\sharp}\mathop{\mathrm{Aut}}(G) < \infty\).
  • Show that given \(\pi: X \rightarrow Y\), \(Y\) is integrally closed in \(K(X)\) over \(K(Y)\) if and only if \({\mathcal{O}}_{Y} \rightarrow \pi_{*} {\mathcal{O}}_{X}\) is an isomorphism (i.e., \(\pi\) is \({\mathcal{O}}\)-connected).
  • Use Tsen’s theorem to show that given a flat family \(X\to Y\) with \(Y\) a curve where the fibers smooth curves of genus 0, this determines a Zariski \({\mathbb{P}}^1{\hbox{-}}\)bundle iff there exists a relative degree 1 line bundle on \(X\) over \(Y\).
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