Centralizing Traces and Lie Triple Isomorphisms on Triangular Algebras

TL;DR

This paper characterizes certain trace functions on triangular algebras and establishes conditions under which Lie triple isomorphisms are almost standard, with applications to triangular matrix and nest algebras.

Contribution

It provides a detailed description of trace functions satisfying specific commutator conditions and characterizes Lie triple isomorphisms on triangular algebras.

Findings

Characterization of trace functions with central commutators

Conditions for Lie triple isomorphisms to be almost standard

Applications to triangular matrix and nest algebras

Abstract

Let $\mathcal{T}$ be a triangular algebra over a commutative ring $\mathcal{R}$ and $\mathcal{Z(T)}$ be the center of $\mathcal{T}$. Suppose that ${\mathfrak q}\colon \mathcal{T}\times \mathcal{T}\longrightarrow \mathcal{T}$ is an $\mathcal{R}$-bilinear mapping and that ${\mathfrak T}_{\mathfrak q}\colon: \mathcal{T}\longrightarrow \mathcal{T}$ is a trace of $\mathfrak{q}$. We describe the form of ${\mathfrak T}_{\mathfrak q}$ satisfying the condition $[{\mathfrak T}_{\mathfrak q}(T), T]\in \mathcal{Z(T)}$ for all $T\in \mathcal{T}$. The question of when ${\mathfrak T}_{\mathfrak q}$ has the proper form will be addressed. Using the aforementioned trace function, we establish sufficient conditions for each Lie triple isomorphism on $\mathcal{T}$ to be almost standard. As applications we characterize Lie triple isomorphisms of triangular matrix algebras and nest algebras. Some further research topics related to current work are proposed at the end of this article.