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arXiv · 1807.05820

Enumerative Galois theory for cubics and quartics

Sam Chow·Rainer Dietmann
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Abstract

We show that there are $O_\varepsilon(H^{1.5+\varepsilon})$ monic, cubic polynomials with integer coefficients bounded by $H$ in absolute value whose Galois group is $A_3$. We also show that the order of magnitude for $D_4$ quartics is $H^2 (\log H)^2$, and that the respective counts for $A_4$, $V_4$, $C_4$ are $O(H^{2.91})$, $O(H^2 \log H)$, $O(H^2 \log H)$. Our work establishes that irreducible non-$S_3$ cubic polynomials are less numerous than reducible ones, and similarly in the quartic setting: these are the first two solved cases of a 1936 conjecture made by van der Waerden.

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Sam Chow, Rainer Dietmann. 2018-07-16. Enumerative Galois theory for cubics and quartics. https://doi.org/10.1016/j.aim.2020.107282

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