Rationality Criteria for Galois Extensions

  • B. Heinrich Matzat
Conference paper
Part of the Mathematical Sciences Research Institute Publications book series (MSRI, volume 16)


Some rationality criteria for finite Galois extensions overℂ(t)are explained. The first rationality criterion and the second rationality criterion, together with the corresponding examples are contained in the forthcoming lecture notes [27] (see also [23—25]). The rationality criteria in sections 4 and 5, the braid orbit theorem, and the twisted braid orbit theorem, are new. With the last one, the Mathieu group M24 is realized as Galois group over ℚ.


Finite Group Conjugacy Class Galois Group Class Structure Class Number 
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Copyright information

© Springer-Verlag New York Inc. 1989

Authors and Affiliations

  • B. Heinrich Matzat
    • 1
  1. 1.Mathematisches Institut IIUniversität Karlsruhe (TH)Karlsruhe 1Federal Republic of Germany

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