30 research outputs found
Integrability and maximally helicity violating diagrams in n=4 supersymmetric yang-mills theory.
We apply maximally helicity violating (MHV) diagrams to the derivation of the one-loop dilatation operator of N=4 supersymmetric Yang-Mills theory in the SO(6) sector. We find that in this approach the calculation reduces to the evaluation of a single MHV diagram in dimensional regularization. This provides the first application of MHV diagrams to an off-shell quantity. We also discuss other applications of the method and future directions
Integrability and unitarity
This article is distributed under the terms of the Creative Commons
Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in
any medium, provided the original author(s) and source are credited.This work was supported by the Science and Technology Facilities Council Consolidated Grant ST/L000415/1
“String theory, gauge theory & duality”
The last of the simple remainders
This article is distributed under the terms of the Creative Commons
Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in
any medium, provided the original author(s) and source are credited
On super form factors of half-BPS operators in N=4 super Yang-Mills
Open Access, (c) The Authors. Article funded by SCOAP3. This article is distributed under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits any use, distribution and reproduction in any medium, provided the original author(s) and source are credited
Tr(F-3) supersymmetric form factors and maximal transcendentality. Part II. 0 < N < 4 super Yang-Mills
The study of form factors has many phenomenologically interesting
applications, one of which is Higgs plus gluon amplitudes in QCD. Through
effective field theory techniques these are related to form factors of various
operators of increasing classical dimension. In this paper we extend our
analysis of the first finite top-mass correction, arising from the operator
, from super Yang-Mills to theories with
, for the case of three gluons and up to two loops. We confirm
our earlier result that the maximally transcendental part of the associated
Catani remainder is universal and equal to that of the form factor of a
protected trilinear operator in the maximally supersymmetric theory. The terms
with lower transcendentality deviate from the answer by a
surprisingly small set of terms involving for example , and
simple powers of logarithms, for which we provide explicit expressions.Comment: Version accepted in JHE
Worldsheet factorization for twistor-strings
We study the multiparticle factorization properties of two worldsheet
theories which--at tree-level--describe the scattering of massless particles in
four dimensions: the Berkovits-Witten twistor-string for N=4 super-Yang-Mills
coupled to N=4 conformal supergravity, and the Skinner twistor-string for N=8
supergravity. By considering these string-like theories, we can study
factorization at the level of the worldsheet before any Wick contractions or
integrals have been performed; this is much simpler than considering the
factorization properties of the amplitudes themselves. In Skinner's
twistor-string this entails the addition of worldsheet gravity as well as a
formalism that represents all external states in a manifestly symmetric way,
which we develop explicitly at genus zero. We confirm that the scattering
amplitudes of Skinner's theory, as well as the gauge theory amplitudes for the
planar sector of the Berkovits-Witten theory, factorize appropriately at genus
zero. In the non-planar sector, we find behavior indicative of conformal
gravity in the Berkovits-Witten twistor-string. We contrast factorization in
twistor-strings with the story in ordinary string theory, and also make some
remarks on higher genus factorization and disconnected prescriptions.Comment: 50 pages, 7 figures. v2: typos corrected and references update