**ODTÜ-B****İ****LKENT
ALGEBRAIC GEOMETRY SEM****I****NAR**

**“****Feynman Integrals as Periods in
Configuration Spaces****”**

** **

by

**ÖZGÜR CEYHAN**

**(****University of Luxembourg****)**

**Abstract: **Mid 90's,
Broadhurst and Kreimer observed that multiple zeta values persist to appear in
Feynman integral computations. Following this observation, Kontsevich proposed
a conceptual explanation, that is, the loci of divergence in these integrals
must be mixed Tate motives. In 2000, Belkale and Brosnan disproved this
conjecture. In this talk, I will describe a way to correct Kontsevich's
proposal and show that the regularized Feynman integrals in position space
setting as well as their ambiguities are given in terms of periods of suitable
configuration spaces, which are mixed Tate. Therefore, the integrals that are
of our interest are indeed Q[1/2πi]-linear combinations of multiple zeta
values. This talk is based on a joint work with M. Marcolli.

** **

**Date:** 05 April 2013, Friday

**Time:** 15.40

**Place:** Bilkent,
Mathematics Seminar Room SA-141

**Tea and cookies will be served before the
talk.**

**You are most cordially invited.**