Radical ideal formulation of the Casas–Alvero conjecture

About 3 years old · traced to

Let KK be an algebraically closed field of characteristic zero, let dd be a positive integer, and let f=xd+a1xd−1+⋯+ad−1x∈K[a1,…,ad−1][x]f=x^d+a_1x^{d-1}+\cdots+a_{d-1}x\in K[a_1,\ldots,a_{d-1}][x]. For i∈{1,…,d−1}i\in\{1,\ldots,d-1\}, let

Ri=Res⁡(f,Hi(f))∈K[a1,…,ad−1],R_i=\operatorname{Res}(f,H_i(f))\in K[a_1,\ldots,a_{d-1}],

where Hi(f)H_i(f) is the ii-th Hasse derivative of ff.

Nullstellensatz formulation of the Casas–Alvero conjecture. The conjecture is equivalent to

(R1,…,Rd−1)=(a1,…,ad−1),\sqrt{(R_1,\ldots,R_{d-1})}=(a_1,\ldots,a_{d-1}),

or, equivalently, there is some N∈NN\in\mathbb{N} such that

aiN∈(R1,…,Rd−1)for all i∈{1,…,d−1}.a_i^N\in(R_1,\ldots,R_{d-1})\quad\text{for all }i\in\{1,\ldots,d-1\}.

This is an algebraic reformulation of the preceding Casas–Alvero conjecture rather than a separate mathematical claim. Over non-algebraically closed fields, the source notes that this formulation is a priori stronger than the corresponding statement about the KK-rational zero set.

References

Primary source

Daniel Schaub and Mark Spivakovsky, “A note on the Casas-Alvero Conjecture”, arXiv:2312.08742 (2025).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.