Zobrazeno 1 - 10
of 60
pro vyhledávání: '"Larsen, Kasper J."'
Publikováno v:
PoS LL2018 (2018) 064
We provide a sufficient condition for avoiding squared propagators in the intermediate stages of setting up differential equations for loop integrals. This condition is satisfied in a large class of two- and three-loop diagrams. For these diagrams, t
Externí odkaz:
http://arxiv.org/abs/1807.01560
Publikováno v:
JHEP 1809 (2018) 024
We present the powerful module-intersection integration-by-parts (IBP) method, suitable for multi-loop and multi-scale Feynman integral reduction. Utilizing modern computational algebraic geometry techniques, this new method successfully trims tradit
Externí odkaz:
http://arxiv.org/abs/1805.01873
Publikováno v:
Phys. Rev. D 98, 025023 (2018)
Integration-by-parts identities between loop integrals arise from the vanishing integration of total derivatives in dimensional regularization. Generic choices of total derivatives in the Baikov or parametric representations lead to identities which
Externí odkaz:
http://arxiv.org/abs/1712.09737
Publikováno v:
PoS RADCOR2017 (2017) 020
Scattering amplitudes computed at a fixed loop order, along with any other object computed in perturbative quantum field theory, can be expressed as a linear combination of a finite basis of loop integrals. To compute loop amplitudes in practice, suc
Externí odkaz:
http://arxiv.org/abs/1712.07510
Autor:
Larsen, Kasper J., Rietkerk, Robbert
Publikováno v:
PoS RADCOR2017 (2017) 021
We present the Mathematica package MultivariateResidues, which allows for the efficient evaluation of multivariate residues based on methods from computational algebraic geometry. Multivariate residues appear in several contexts of scattering amplitu
Externí odkaz:
http://arxiv.org/abs/1712.07050
Publikováno v:
Phys. Rev. D 97, 105014 (2018)
We present a proof that differential equations for Feynman loop integrals can always be derived in Baikov representation without involving dimension-shift identities. We moreover show that in a large class of two- and three-loop diagrams it is possib
Externí odkaz:
http://arxiv.org/abs/1712.03760
Publikováno v:
Comput.Phys.Commun. 221 (2017) 203-215
For any given Feynman graph, the set of integrals with all possible powers of the propagators spans a vector space of finite dimension. We introduce the package {\sc Azurite} ({\bf A ZUR}ich-bred method for finding master {\bf I}n{\bf TE}grals), whic
Externí odkaz:
http://arxiv.org/abs/1612.04252
Autor:
Larsen, Kasper J., Zhang, Yang
Publikováno v:
PoS(LL2016)029
Integration-by-parts reductions play a central role in perturbative QFT calculations. They allow the set of Feynman integrals contributing to a given observable to be reduced to a small set of basis integrals, and they moreover facilitate the computa
Externí odkaz:
http://arxiv.org/abs/1606.09447
Autor:
Larsen, Kasper J.
The study of scattering amplitudes beyond one loop is necessary for precision phenomenology for the Large Hadron Collider and may also provide deeper insights into the theoretical foundations of quantum field theory. In this thesis we develop a new m
Externí odkaz:
http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-179203
Autor:
Larsen, Kasper J., Zhang, Yang
Publikováno v:
Phys. Rev. D 93, 041701 (2016)
We show that the integration-by-parts reductions of various two-loop integral topologies can be efficiently obtained by applying unitarity cuts to a specific set of subgraphs and solving associated polynomial (syzygy) equations.
Comment: 5 pages
Comment: 5 pages
Externí odkaz:
http://arxiv.org/abs/1511.01071