Classification of Homogeneous Odd Rota--Baxter Operators on a Modified Witt-Type Lie Superalgebra
Mohsen Ben Abdallah, Marwa Ennaceur
TL;DR
The paper tackles the problem of classifying homogeneous odd Rota--Baxter operators of weight zero on a modified Witt-type Lie superalgebra W with bracket deformation [L_m,G_n]=(m-n-1)G_{m+n}. It develops a homogeneous-decomposition framework, derives coupled functional equations for the odd component, and proves a complete dichotomy: either g≡0 with arbitrary f, or g≠0 forcing f≡0 and g to take rigid forms dependent on an odd integer k, including both finite and infinite support cases. It further shows all derivations of W are inner, no RB operator is invertible, and constructs induced super pre-Lie and dendriform structures with a cohomological interpretation; explicit r-matrix connections to Yang–Baxter theory are discussed, highlighting potential links to integrable systems. Overall, the modification by -1 in the mixed bracket enriches the landscape of odd RB operators, revealing new infinite-support solutions and a broader parameter space than in the standard Witt superalgebras. These results lay groundwork for exploring deformed Witt-type algebras in representation theory and integrable hierarchies.
Abstract
We classify all homogeneous odd (i.e., parity-reversing) Rota--Baxter operators of weight zero on the modified Witt-type Lie superalgebra $W = \langle L_m, G_n \rangle_{m,n\in\Z}$. Our classification shows that nontrivial such operators are highly constrained: either $g \equiv 0$ and $f$ is arbitrary, or $g \not\equiv 0$ forces $f \equiv 0$, and $g$ must take one of several rigid forms dictated by the integer shift $k$ (necessarily odd when $g(0) \neq 0$). We prove that every Rota--Baxter operator on $W$ decomposes uniquely into even and odd homogeneous components; we restrict our attention to the odd case, which yields the full nontrivial structure. Furthermore, we show that all derivations of $W$ are inner, that no Rota--Baxter operator on $W$ is invertible, and we describe the induced super pre-Lie algebra structure together with its cohomological interpretation.
