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arXiv · 1208.5404

Constraints on counterexamples to the Casas-Alvero conjecture, and a verification in degree 12

Wouter Castryck·Robert Laterveer·Myriam Ounaïes
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Abstract

In a first (theoretical) part of this paper, we prove a number of constraints on hypothetical counterexamples to the Casas-Alvero conjecture, building on ideas of Graf von Bothmer, Labs, Schicho and van de Woestijne that were recently reinterpreted by Draisma and de Jong in terms of $p$-adic valuations. In a second (computational) part, we present ideas improving upon Diaz-Toca and Gonzalez-Vega's Gröbner basis approach to the Casas-Alvero conjecture. One application is an extension of the proof of Graf von Bothmer et al. to the cases $5p^k$, $6p^k$ and $7p^k$ (that is, for each of these cases, we elaborate the finite list of primes $p$ for which their proof is not applicable). Finally, by combining both parts, we settle the Casas-Alvero conjecture in degree 12 (the smallest open case).

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Wouter Castryck, Robert Laterveer, Myriam Ounaïes. 2012-08-27. Constraints on counterexamples to the Casas-Alvero conjecture, and a verification in degree 12. https://arxiv.org/abs/1208.5404

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