Carpet Lie Rings Not Invariant with Respect to Carpet Subgroups
摘要
This article is a continuation of the author’s papers[Proc. Steklov Inst. Math., 2013; J. Sib. Fed. Univ. Math. Phys., 2023; Sib. Math. J., 2026].In the first of them, necessary and sufficient conditions for a carpet Lie ring to be invariant with respect to a carpet subgroup were found, whereas in the second and third papers it was established that these conditions are sufficient for the original carpet to be closed.Here we construct examples of irreducible closed carpets over a field such that the carpet Lie rings are not invariant with respect to the corresponding carpet subgroups; at the same time, depending on the type of the root system associated with the carpet, some restrictions are imposed on the characteristic of the field, and, in particular, if the characteristic of the field is at least