Speaker
Oliver Schnetz
Description
The periods of primitive divergent phi4 graphs are renormalization scheme independent contributions to the phi4 beta
function. They are mathematical periods in the sense of Kontsevich and Zagier. By general principles there exists a
Galois coaction on these numbers. Recently it has become possible to calculate more than 300 distinct periods of
graphs up to 11 loops. The analysis of these data leads to two (possibly false) conjectures on the coaction
structure of phi4 periods.
