The c(2) invariant is invariant

Abstract

The c(2) invariants in all 4 different representations of the Feynman period (parametric and dual parametric representations, position and momentum spaces) coincide for all log-divergent graphs that satisfy the condition called duality admissibility. We check this condition for a good subspace of graphs with certain combinatorial properties, for instance, for all planar graphs. After the result in [14], the coincidence holds for all physically relevant graphs. (c) 2017 International Press of Boston, Inc.