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Related papers: One-loop four-graviton amplitudes in N=4 supergrav…

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We construct the three-loop four-point amplitude of N=8 supergravity using the unitarity method. The amplitude is ultraviolet finite in four dimensions. Novel cancellations, not predicted by traditional superspace power-counting arguments,…

High Energy Physics - Theory · Physics 2008-11-26 Z. Bern , J. J. Carrasco , L. J. Dixon , H. Johansson , D. A. Kosower , R. Roiban

Generalised unitarity techniques are used to calculate the coefficients of box and triangle integral functions of one-loop gluon scattering amplitudes in gauge theories with $N < 4$ supersymmetries. We show that the box coefficients in N=1…

High Energy Physics - Theory · Physics 2008-11-26 Steven J. Bidder , N. E. J. Bjerrum-Bohr , David C. Dunbar , Warren B. Perkins

We evaluate one-loop amplitudes of N = 4 supergravity in D dimensions using the double-copy procedure that expresses gravity integrands in terms of corresponding ones in Yang--Mills theory.We organize the calculation in terms of a set of…

High Energy Physics - Theory · Physics 2017-11-21 Zvi Bern , Alex Edison , David Kosower , Julio Parra-Martinez

The one-loop correction to eleven-dimensional supergravity involves a cubically divergent term $t_8t_8R^4$, with four Riemann tensors. A similar term (with finite coefficient) has been argued to be present in the M-theory effective action.…

High Energy Physics - Theory · Physics 2026-03-04 Aviral Aggarwal , Subhroneel Chakrabarti , Steven Weilong Hsia , Ahmed Rakin Kamal , Linus Wulff

The infrared singularities of gravitational amplitudes are one-loop exact, in that higher-loop divergences are characterized by the exponential of the one-loop divergence. We show that the contributions to SU(N) gauge-theory amplitudes that…

High Energy Physics - Theory · Physics 2015-06-12 Stephen G. Naculich , Horatiu Nastase , Howard J. Schnitzer

A first quantised approach to loop amplitudes based on the pure spinor particle is applied to the systematics of four-particle amplitudes in maximally supersymmetric field theories. Counting of fermionic zero modes allows the identification…

High Energy Physics - Theory · Physics 2011-03-28 Jonas Bjornsson , Michael B. Green

We bootstrap loop corrections to AdS${}_5$ supergravity amplitudes by enforcing the consistency of the known classical results with the operator product expansion of $\mathcal{N}=4$ super Yang-Mills theory. In particular this yields much…

High Energy Physics - Theory · Physics 2018-02-14 F. Aprile , J. M. Drummond , P. Heslop , H. Paul

We consider the finite part of the leading local interactions in the low energy expansion of the four graviton amplitude from the ladder skeleton diagrams in maximal supergravity on T^2, at three and four loops. At three loops, we express…

High Energy Physics - Theory · Physics 2015-09-30 Anirban Basu

The anti-de Sitter/conformal field theory duality conjecture raises the question of how the perturbative expansion in the conformal field theory can resum to a simple function. We exhibit a relation between the one-loop and two-loop…

High Energy Physics - Theory · Physics 2017-08-23 C. Anastasiou , Z. Bern , L. J. Dixon , D. A. Kosower

We investigate the relation between 4d ambitwistor string theory and on-shell diagrams for planar N=4 super-Yang-Mills and N=8 supergravity, and deduce several new results about their scattering amplitudes at tree-level and 1-loop. In…

High Energy Physics - Theory · Physics 2017-09-13 Joseph A. Farrow , Arthur E. Lipstein

We calculate the supergravity fields sourced by a D-brane with a null travelling wave from disk amplitudes in type IIB string theory compactified on T^4 x S^1. The amplitudes reproduce all the non-trivial features of the previously known…

High Energy Physics - Theory · Physics 2010-12-08 William Black , Rodolfo Russo , David Turton

Recently, the spinor helicity formalism and on-shell superspace were developed for six-dimensional gauge theories with (1,1) supersymmetry. We combine these two techniques with (generalised) unitarity, which is a powerful technique to…

High Energy Physics - Theory · Physics 2011-03-02 Andreas Brandhuber , Dimitrios Korres , Daniel Koschade , Gabriele Travaglini

The overall coefficient of the two-loop 4-particle amplitude in superstring theory is determined by making use of the factorization and unitarity. To accomplish this we computed in detail all the relevant tree and one-loop amplitudes…

High Energy Physics - Theory · Physics 2009-11-11 Zhi-Guang Xiao , Chuan-Jie Zhu

We show, for previously uncalculated examples containing a uniform mass in the loop, that it is possible to obtain complete massive one-loop gauge theory amplitudes solely from unitarity and known ultraviolet or infrared mass singularities.…

High Energy Physics - Phenomenology · Physics 2008-11-26 Z. Bern , A. G. Morgan

The recent progress in computing gauge theory amplitudes can be extended, in many cases, to theories incorporating gravity. This has improved our understanding of the perturbative expansion of N=8 supergravity supporting the ``no-triangle…

High Energy Physics - Theory · Physics 2011-04-11 N. E. J. Bjerrum-Bohr , David C. Dunbar , Harald Ita

Multi-loop superstring amplitude are calculated in the convenient gauge where Grassmann moduli are carried by the 2D gravitino field. Generally, instead of the modular symmetry, the amplitudes hold the symmetry under modular transformations…

High Energy Physics - Theory · Physics 2012-11-15 G. S. Danilov

The monodromy relations in string theory provide a powerful and elegant formalism to understand some of the deepest properties of tree-level field theory amplitudes, like the color-kinematics duality. This duality has been instrumental in…

High Energy Physics - Theory · Physics 2017-07-24 Piotr Tourkine , Pierre Vanhove

The massless 4-point one-loop amplitude computation in the pure spinor formalism is shown to agree with the computation in the RNS formalism.

High Energy Physics - Theory · Physics 2009-11-11 Carlos R. Mafra

All four-point mixed gluon-graviton amplitudes in pure Einstein-Yang-Mills theory with at most one state of negative helicity are computed at one-loop order and maximal powers of the gauge coupling using D-dimensional generalized unitarity.…

High Energy Physics - Theory · Physics 2018-09-26 Dhritiman Nandan , Jan Plefka , Gabriele Travaglini

We propose a new ``universal expansion" for one-loop amplitudes with arbitrary number of gluons in $D$ dimensions, which holds for general gauge theories with gluons/fermions/scalars in the loop, including pure and supersymmetric Yang-Mills…

High Energy Physics - Theory · Physics 2024-12-30 Qu Cao , Jin Dong , Song He , Fan Zhu