Deligne's companions conjecture for normal varieties
Let be a finite field of characteristic , let be a connected normal variety over , let be a prime, and let be an irreducible Weil lisse -sheaf over with finite-order determinant. Let be the number field generated by the coefficients of the Frobenius polynomials of at closed points. A Weil lisse -sheaf is -compatible with when it has the same Frobenius polynomials under the embedding determined by the finite place . Companions conjecture. After possibly replacing with a finite extension, for every finite place not dividing there exists a Weil lisse -sheaf -compatible with . This conjecture extends the known companion results for smooth varieties to normal varieties; the paper studies the obstruction in the singular case and proves it for some singular normal varieties. The status of the conjecture in general is open.
References
Primary source
Marco D'Addezio, “Some remarks on the companions conjecture for normal varieties”, arXiv:2006.09954 (2020).
Additional references
4 papers in this index state this conjecture (2017–2020). The statement above is taken from the most recent of them; the others are arXiv:1811.00204, arXiv:1809.02106, arXiv:1711.04797.
Progress summary
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.