The Complexity of Computing all Subfields of an Algebraic Number Field

  title={The Complexity of Computing all Subfields of an Algebraic Number Field},
  author={Jonas Szutkoski and M. V. Hoeij},
  journal={J. Symb. Comput.},
For a finite separable field extension K/k, all subfields can be obtained by intersecting so-called principal subfields of K/k. In this work we present a way to quickly compute these intersections. If the number of subfields is high, then this leads to faster run times and an improved complexity. 

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