Strong inductive Giannelli–McKay condition for quasisimple groups

About 1 year old · traced to

Let SS be a quasisimple group with cyclic center, let pp be a prime, let P∈Syl⁡p(S)P\in\operatorname{Syl}_p(S), and set A=Aut⁡(S)PA=\operatorname{Aut}(S)_P. For χ∈Irr⁡p′(S)\chi\in\operatorname{Irr}_{p'}(S), write AχA_\chi for its stabilizer in AA, and let ≥c\geq_c denote the central-isomorphism relation on character triples. Strong inductive Giannelli–McKay condition. There should exist an AA-equivariant bijection

Ψ:Irr⁡p′(S)⟶Irr⁡p′(NS(P))\Psi:\operatorname{Irr}_{p'}(S)\longrightarrow\operatorname{Irr}_{p'}(N_S(P))

such that Ψ(χ)(1)≤χ(1)\Psi(\chi)(1)\leq\chi(1) and

(S⋊Aχ,S,χ)≥c(NS(P)⋊Aχ,NS(P),Ψ(χ))(S\rtimes A_\chi,S,\chi)\geq_c(N_S(P)\rtimes A_\chi,N_S(P),\Psi(\chi))

for every χ∈Irr⁡p′(S)\chi\in\operatorname{Irr}_{p'}(S). This is a stronger version of the inductive condition, obtained in the cases treated in the paper. The source reports verification for exceptional Lie type in all primes and for groups of Lie type in defining characteristic, and consequently for all quasisimple groups when p=2p=2, but does not establish the condition in full generality.

References

Primary source

Nguyen N. Hung, J. Miquel Martínez and Gabriel Navarro, “Sum of the squares of the p'-character degrees”, arXiv:2505.21267 (2026).

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.