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MAU34106 Galois theory

Module Code MAU34106
Module Title Galois theory
Semester taught Semester 2
ECTS Credits 5
Module Lecturer Prof. Adam Keilthy
Module Prerequisites MAU22102 Fields, rings and modules

Assessment Details

  • This module is examined in a 2-hour examination at the end of Semester 1.
  • Continuous assessment contributes 20% towards the overall mark.
  • The module is passed if the overall mark for the module is 40% or more. If the overall mark for the module is less than 40% and there is no possibility of compensation, the module will be reassessed as follows: 
    1) A failed exam in combination with passed continuous assessment will be reassessed by an exam in the supplemental session; 
    2) The combination of a failed exam and failed continuous assessment is reassessed by the supplemental exam; 
    3) A failed continuous assessment in combination with a passed exam will be reassessed by one or more summer assignments in advance of the supplemental session.

Contact Hours

11 weeks of teaching with 3 lectures per week.

Learning Outcomes

On successful completion of this module, students will be able to

  • State and explain relationships between properties of field extensions and properties of their automorphism groups.
  • Explicitly construct finite fields of small orders.
  • Determine Galois groups of polynomials of small degree.
  • Illustrate applications of Galois theory on specific examples.

Module Content

  • Polynomial rings: UFD and PID property, Gauss lemma, Eisenstein's criterion.
  • Algebraic field extensions: Tower law, ruler and compass constructions.
  • Splitting fields and their properties, classification of finite fields.
  • Normal and separable extensions, primitive element theorem.
  • Galois extension, Galois correspondence, fundamental theorem of algebra.
  • Algorithm for computing the Galois group of a given polynomial.
  • Solvability by radicals. Cyclic, abelian and solvable field extensions.
  • Abel's theorem for equations of degree five.
  • Abelian and cyclotomic extensions, Kronecker-Weber theorem.