Sean Eberhard (3), Francesca Lisi (3), Marco Barbieri (2), Andrea Lucchini (2), Pablo Spiga (2), Daniele Dona (1), Elena Maini (1), Patricia Medina Capilla (1), Mima Stanojkovski (1), Gareth Tracey (1)
On the left is the Foster graph (for its significance in my research, see Theorem 1.1 here).
Cayley graphs of quasirandom groups
We extend recent work of Golsefidy-Srinivas, concluding that expansion in a quasirandom group is always controlled by expansion in its simple quotients. Then, we extend some results for simple groups of bounded Lie rank to abstract quasirandom groups.
arxiv (2026, 20pp)
The base size of vertex-transitive cubic graphs
with Marco Barbieri and Pablo SpigaWe prove that, except for some small cases and a natural infinite family, all connected vertex-transitive cubic graphs have base size at most 2, i.e. fixing two vertices can break all symmetries.
arxiv (2026, 37pp)
Diameter bounds for arbitrary finite groups and applications
with Sean Eberhard, Elena Maini and Gareth TraceyWe prove a polylog-type diameter bound for arbitrary finite groups, which essentially was an untouched problem. There are several notable applications.
arxiv (2026, 35pp)
Expanding groups with large diameter
with Sean EberhardWe exhibit a sequence of finite groups with very different Cayley graphs, namely expanders and with non-polylog diameter. This answers a question of Pyber and Szabó from 2013.
arxiv (2026, 8pp)
On the maximal subgroups of almost simple and primitive perfect groups
with Patricia Medina CapillaWe prove that every maximal subgroup of every finite almost simple group is nearly perfect, in the sense that the 10th term of its derived series is always perfect. In fact we obtain the same result for primitive perfect groups.
arxiv (2026, 14pp)
Groups that produce expander graphs
A survey on groups whose Cayley/Schreier graphs are good candidate to be expanders. There are minor new results.
arxiv (2025, 11pp)
Exponent and number of generators in a finite group
We observe that the number of generatos of a finite group can be bounded by the ratio between the order and the exponent.
arxiv (2025, 3pp)
14. Sylow subgroups for distinct primes and intersection of nilpotent subgroups, J. Algebra (2026)
with Francesca Lisi5. The growth of abelian sections, Ann. Mat. Pura Appl. (2023)
On finite groups with polynomial diameter
We make an observation concerning a deep theorem of Breuillard and Tointon.
arxiv (2021, 4pp)
1. A subexponential bound on the cardinality of abelian quotients in finite transitive groups, Bull. London Math. Soc. (2021)
with Andrea Lucchini and Pablo Spiga