# The Complexity of Computing all Subfields of an Algebraic Number Field

@article{Szutkoski2019TheCO, title={The Complexity of Computing all Subfields of an Algebraic Number Field}, author={Jonas Szutkoski and M. V. Hoeij}, journal={J. Symb. Comput.}, year={2019}, volume={93}, pages={161-182} }

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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