3 papers
math.AG2026
The Tate conjecture for powers of abelian fourfolds and the Hodge conjecture for powers of CM fourfolds
Ningyi Li
We prove the Tate conjecture in every codimension on every power of an abelian variety of dimension at most four over a finite field. For geometrically simple fourfolds, we use Bro…
math.NT2026
The Tate conjecture for abelian fivefolds over finite fields
Ningyi Li
We prove the Tate conjecture for abelian fivefolds over finite fields. The proof constructs correspondences for a residual motive using a Moret--Bailly family, Gross--Schoen height…
math.QA2026
Exponents of factorized groups and Kashina's conjecture for group-theoretical Hopf algebras
Ningyi Li
Let be a factorization of a finite group, with neither factor assumed normal and with allowed to be nontrivial. We prove that divides $\operatorname{lcm}(…