Cohomology of Schemes

Definitions

  • What is a flasque sheaf?
  • What is a fine sheaf?
  • What is the Godemont resolution?
  • What is the higher direct image?
  • What is the higher pushforward?
  • What is an abelian category?
  • What is a delta functor?
  • What is the dualizing sheaf?
  • What is the module of relative differential forms?
  • What is the sheaf of differentials?
  • What is the geometric genus?
  • What is the canonical class?
  • What is the Chow ring?
  • What is the cycle class map?

Results

  • Why does the category of sheaves of \({\mathcal{O}}_X\) modules have enough injectives?
  • What is Serre’s vanishing characterization of affine schemes among Noetherian schemes?
  • What is the theorem on formal functions?
  • What is the semicontinuity theorem?
  • How is the sheaf of differentials related to the singularities/smoothness of a scheme?
  • What is Bertini’s theorem?
  • Show that singular cohomology is isomorphic to Cech cohomology for Noetherian separated schemes.
  • What is the cohomological criterion for ampleness?
  • Show that the dualizing sheaf is isomorphic to the canonical sheaf for nonsingular projective varieties.
  • What is the Lefschetz hyperplane theorem
  • What is Hodge duality?
  • What is Serre duality?
  • What is Grothendieck vanishing?
  • What is Serre’s vanishing theorem?

Problems

  • Compute the Cech cohomology of ${\mathbb{P}}^n_{/ {k}} $.
  • Compute \(H^*(X, {\mathcal{O}}_X)\) for $X = {\mathbb{P}}^n_{/ {k}} $.
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