Computing subfields: Reverse of the primitive element problem

  • D. Lazard
  • A. Valibouze
Part of the Progress in Mathematics book series (PM, volume 109)


We describe an algorithm which computes all subfields of an effectively given finite algebraic extension. Although the base field can be arbitrary, we focus our attention on the rationals.

This appears to be a fundamental tool for the simplification of algebraic numbers.


Symmetric Group Symmetric Function Galois Group Monomial Form Algebraic Number 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Birkhäuser Boston 1993

Authors and Affiliations

  • D. Lazard
    • 1
  • A. Valibouze
    • 1
  1. 1.LITPUniversité P. et M. CurieParis Cedex 05France

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