Skip to main content Skip to navigation

MA4J7 Content

Content:

  • Cochain complexes and cohomology
  • The duality between homology and cohomology
  • Chain approximations to the diagonal and products in cohomology
  • The cohomology ring
  • The cohomology ring of a product of spaces and applications
  • The PoincarĂ© duality theorem
  • The cohomology ring of projective spaces and applications
  • The Hopf invariant and the Hopf maps
  • Spaces with polynomial cohomology
  • Further applications of cohomology

Aims:

  • To introduce cohomology and products as an important tool in topology
  • Give a proof of the PoincarĂ© duality theorem and go on to use this theorem to compute products
  • There will be many applications of products including using products to distinguish between spaces with isomorphic homology groups
  • To use products to study the classical Hopf maps

Objectives: By the end of the module the student should be able to:

  • Define cup and cap products
  • Use the PoincarĂ© duality theorem
  • Compute the cohomology ring of many spaces including product spaces and projective spaces
  • Apply the cohomology ring to get topological results
  • Define, calculate and apply the Hopf invariant

Books:
Algebraic Topology, Allen Hatcher, CUP 2002
Algebraic Topology A First Course, Greenberg and Harper, Addison-Wesley 1981