4 papers
Towards cohomology of renormalization: bigrading the combinatorial Hopf algebra of rooted trees
D. J. Broadhurst, D. Kreimer
The renormalization of quantum field theory twists the antipode of a noncocommutative Hopf algebra of rooted trees, decorated by an infinite set of primitive divergences. The Hopf…
Combinatoric explosion of renormalization tamed by Hopf algebra: 30-loop Pade-Borel resummation
D. J. Broadhurst, D. Kreimer
It is easy to sum chain-free self-energy rainbows, to obtain contributions to anomalous dimensions. It is also easy to resum rainbow-free self-energy chains. Taming the combinatori…
Feynman diagrams as a weight system: four-loop test of a four-term relation
D. J. Broadhurst, D. Kreimer
At four loops there first occurs a test of the four-term relation derived by the second author in the course of investigating whether counterterms from subdivergence-free diagrams…
Heavy-Higgs Lifetime at Two Loops
A. Frink, B. A. Kniehl, D. Kreimer +1
The Standard-Model Higgs boson with mass decays almost exclusively to pairs of and bosons. We calculate the dominant two-loop corrections of $ O( G_F^2 M_H^…