Four Loop Massless Propagators: an Algebraic Evaluation of All Master Integrals
Abstract
The old "glue--and--cut" symmetry of massless propagators, first established in [1], leads --- after reduction to master integrals is performed --- to a host of non-trivial relations between the latter. The relations constrain the master integrals so tightly that they all can be analytically expressed in terms of only few, essentially trivial, watermelon-like integrals. As a consequence we arrive at explicit analytical results for all master integrals appearing in the process of reduction of massless propagators at three and four loops. The transcendental structure of the results suggests a clean explanation of the well-known mystery of the absence of even zetas (zeta_{2n}) in the Adler function and other similar functions essentially reducible to the massless propagators. Once a reduction of massless propagators at five loops is available, our approach should be also applicable for explicit performing the corresponding five-loop master integrals.
Cite
@article{arxiv.1004.1153,
title = {Four Loop Massless Propagators: an Algebraic Evaluation of All Master Integrals},
author = {P. A. Baikov and K. G. Chetyrkin},
journal= {arXiv preprint arXiv:1004.1153},
year = {2015}
}
Comments
34 pages, few typos have been fixed, references and acknowledgements have been updated. Results for master integrals (together with some auxiliary information) are now available in http://www-ttp.physik.uni-karlsruhe.de/Progdata/ttp10/ttp10-18.