Co-Poisson structures on polynomial Hopf algebras

Abstract

The Hopf dual $H^{\circ }$ of any Poisson Hopf algebra $H$ is proved to be a co-Poisson Hopf algebra provided $H$ is noetherian. Without noetherian assumption, it is not true in general. There is no nontrivial Poisson Hopf structure on the universal enveloping algebra of a non-abelian Lie algebra. The Poisson Hopf structures on $A=k[x_1,x_2,\cdots ,x_d]$, viewed as the universal enveloping algebra of a finite-dimensional abelian Lie algebra, are exactly linear Poisson structures on $A$. The co-Poisson structures on polynomial Hopf algebra $A$ are characterized. Some correspondences between co-Poisson and Poisson structures are also established.

This paper has been accepted for publication in SCIENCE CHINA Mathematics