Abstract
Let K be a field and let G be a finite group. G is K-admissible if there exists a Galois extension L of K with G=Gal(L/K) such that L is a maximal subfield of a central K-division algebra. We characterize those number fields K such that H is K-admissible where H is any subgroup of SL(2, 5) which contains a S 2-group. The method also yields refinements and alternate proofs of some known results including the fact that A 5 is K-admissible for every number field K.
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Dedicated to Professor Jacques Tits on the occasion of his sixtieth birthday
The first author was partly supported by NSF fellowship DMS-8601130; the second author was partly supported by NSF grant DMS-8806371.
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Feit, P., Feit, W. The K-admissibility of SL(2, 5). Geom Dedicata 36, 1–13 (1990). https://doi.org/10.1007/BF00181462
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DOI: https://doi.org/10.1007/BF00181462