Jordan maps and zero Lie product determined algebras

Abstract

Let $A$ be an algebra over a field $F$ with {\rm char}$(F)\ne 2$. If $A$ is generated as an algebra by $[[A,A],[A,A]]$, then for every skew-symmetric bilinear map $\Phi :A\times A\to X$, where $X$ is an arbitrary vector space over $F$, the condition that $\Phi (x^2,x)=0$ for all $x\in A$ implies that $\Phi (xy,z)+\Phi (zx,y)+\Phi (yz,x)=0$ for all $x,y,z\in A$. This is applicable to the question of whether $A$ is zero Lie product determined, and is also used in proving that a Jordan homomorphism from $A$ onto a semiprime algebra $B$ is the sum of a homomorphism and an antihomomorphism.