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arXiv · 0812.2419

Rooted trees and symmetric functions: Zhao's homomorphism and the commutative hexagon

Michael E. Hoffman
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Abstract

Recent work on perturbative quantum field theory has led to much study of the Connes-Kreimer Hopf algebra. Its (graded) dual, the Grossman-Larson Hopf algebra of rooted trees, had already been studied by algebraists. L. Foissy introduced a noncommutative version of the Connes-Kreimer Hopf algebra, which turns out to be self-dual. Using some homomorphisms defined by the author and W. Zhao, we describe a commutative diagram that relates the aforementioned Hopf algebras to each other and to the Hopf algebras of symmetric functions, noncommutative symmetric functions, and quasi-symmetric functions.

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Michael E. Hoffman. 2008-12-12. Rooted trees and symmetric functions: Zhao's homomorphism and the commutative hexagon. https://arxiv.org/abs/0812.2419

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