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abstract: 'Multiple zeta values (MZVs) in the usual sense are the special values of multiple variable zeta functions at positive integers. Their extensive studies are important in both mathematics and physics with broad connections and applications. In contrast, very little is known about the special values of multiple zeta functions at non-positive integers since the values are usually singular. We define and study multiple zeta functions at integer values by adapting methods of renormalization from quantum field theory, and following the Hopf algebra approach of Connes and Kreimer. This definition of renormalized MZVs agrees with the convergent MZVs and extends the work of Ihara-Kaneko-Zagier on renormalization of MZVs with positive arguments. We further show that the important quasi-shuffle (stuffle) relation for usual MZVs remains true for the renormalized MZVs.'
address:
- 'Department of Mathematics and Computer Science, Rutgers University, Newark, NJ 07102'
- 'Max Planck Institute for Mathematics, Vivatsgasse 7, D-53111 Bonn, Germany; Yangtze Center of Mathematics, Sichuan University, Chengdu, 610064, P. R. China '
author:
- Li Guo
- Bin Zhang
title: Renormalization of multiple zeta values
---

Introduction
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Multiple zeta values (MZVs), as we know in the current literature, are defined to be the values of 