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arXiv · 1511.06871

Rigidity for F_4(p)

Frank Lübeck·Robert Guralnick·Jun Yu
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Abstract

We prove the existence of certain rationally rigid triples in F_4(p) for good primes p (i.e., p>3), thereby showing that these groups occur as regular Galois groups over Q(t) and so also over Q. We show that these triples give rise to rigid triples in the algebraic group and prove that they generate an interesting subgroup in characteristic 0.

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Frank Lübeck, Robert Guralnick, Jun Yu. 2015-12-05. Rigidity for F_4(p). https://doi.org/10.1016/j.aim.2016.07.015

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