Rota-Baxter operators of nilpotent evolution algebras with maximal nilindex
Izzat Qaralleh, Farrukh Mukhamedov, Otabek Khakimov
TL;DR
This work classifies Rota-Baxter operators of weights $0$ and $1$ on nilpotent evolution algebras of maximal nilindex. By reducing to upper-triangular operators in a natural basis, the authors obtain a complete description: weight $0$ operators are rigid and essentially diagonal up to last-column perturbations, while weight $1$ operators split into triangular and non-triangular regimes with the diagonal entries governed by the rational map $f(x)=\frac{x^2}{2x+1}$ and periodicity phenomena. The triangular RB$_1$ regime yields explicit normal forms and period constraints, whereas the non-triangular RB$_1$ regime forces diagonals to be either $0$ or $-1$ with precise coefficient recursions. Overall, the paper provides a comprehensive, dynamical-systems–influenced classification of RB operators on this extremal class of evolution algebras, highlighting a sharp dichotomy between weights $0$ and $1$.
Abstract
Nilpotent evolution algebras of maximal nilindex admit a natural basis in which the structure matrix is strictly upper triangular. In this paper we classify Rota{Baxter operators of weights zero and one on such algebras. We prove that every Rota{Baxter operator is upper triangular with respect to a natural basis. For weight zero, a strong rigidity phenomenon occurs: the operators are diagonal up to possible perturbations supported in the last basis vector. For weight one, a richer structure appears, including both triangular and non-triangular families, with the diagonal entries governed by a rational recurrence relation. Our results provide a complete description of Rota{Baxter operators on nilpotent evolution algebras of maximal nilindex.
