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Related papers: Is N = 8 Supergravity Ultraviolet Finite?

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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

We describe the construction of the complete four-loop four-particle amplitude of N=8 supergravity. The amplitude is ultraviolet finite, not only in four dimensions, but in five dimensions as well. The observed extra cancellations provide…

High Energy Physics - Theory · Physics 2015-03-13 Z. Bern , J. J. Carrasco , L. J. Dixon , H. Johansson , R. Roiban

In this lecture we summarize recent calculations pointing to the possible ultraviolet finiteness of N = 8 supergravity in four dimensions. We outline the modern unitarity method, which enables multiloop calculations in this theory and…

High Energy Physics - Theory · Physics 2009-03-02 Z. Bern , J. J. M. Carrasco , H. Johansson

Recent computations of scattering amplitudes show that N=8 supergravity is surprisingly well behaved in the ultraviolet and may even be ultraviolet finite in perturbation theory. The novel cancellations necessary for ultraviolet finiteness…

High Energy Physics - Theory · Physics 2015-03-13 Z. Bern , J. J. Carrasco , D. Forde , H. Ita , H. Johansson

In these lectures I describe the remarkable ultraviolet behavior of N=8 supergravity, which through four loops is no worse than that of N=4 super-Yang-Mills theory (a finite theory). I also explain the computational tools that allow…

High Energy Physics - Theory · Physics 2015-03-17 Lance J. Dixon

The 4-loop 4-point amplitude in N=8 d=4 supergravity is UV finite due to supersymmetry. Even better UV behavior of the 4-loop 4-point amplitude, analogous to that of N=4 SYM theory, has been recently established by computation in [1]. All…

High Energy Physics - Theory · Physics 2009-10-02 Renata Kallosh

We show that the four-loop four-point amplitudes of N = 5 supergravity are ultraviolet finite in four dimensions, contrary to expectations based on supersymmetry and duality-symmetry arguments. We explain why the diagrams of any covariant…

High Energy Physics - Theory · Physics 2014-11-19 Zvi Bern , Scott Davies , Tristan Dennen

Using the method of maximal cuts, we construct the complete D-dimensional integrand of the five-loop four-point amplitude of N = 4 super-Yang-Mills theory, including nonplanar contributions. In the critical dimension where this amplitude…

High Energy Physics - Theory · Physics 2015-03-20 Z. Bern , J. J. M. Carrasco , H. Johansson , R. Roiban

String theory implies that field theories containing gravity are in a certain sense `products' of gauge theories. We make this product structure explicit up to two loops for the relatively simple case of N=8 supergravity four-point…

High Energy Physics - Theory · Physics 2010-11-15 Z. Bern , L. Dixon , D. C. Dunbar , M. Perelstein , J. S. Rozowsky

We argue that recent results in string perturbation theory indicate that the four-graviton amplitude of four-dimensional N=8 supergravity might be ultraviolet finite up to eight loops. We similarly argue that the h-loop M-graviton amplitude…

High Energy Physics - Theory · Physics 2008-11-26 Michael B. Green , Jorge G. Russo , Pierre Vanhove

In this contribution we describe computational tools that permit the evaluation of multi-loop scattering amplitudes in N=8 supergravity, in terms of amplitudes in N=4 super-Yang-Mills theory. We also discuss the remarkable ultraviolet…

High Energy Physics - Theory · Physics 2015-05-27 Zvi Bern , John Joseph Carrasco , Lance Dixon , Henrik Johansson , Radu Roiban

We demonstrate that pure N=4 supergravity is ultraviolet divergent at four loops. The form of the divergence suggests that it is due to the rigid U(1) duality-symmetry anomaly of the theory. This is the first known example of an ultraviolet…

High Energy Physics - Theory · Physics 2013-12-16 Zvi Bern , Scott Davies , Tristan Dennen , Alexander V. Smirnov , Vladimir A. Smirnov

We show that N = 8 supergravity may possess an even larger symmetry than previously believed. Such an enhanced symmetry is needed to explain why this theory of gravity exhibits ultraviolet behaviour reminiscent of the finite N = 4…

High Energy Physics - Theory · Physics 2020-02-25 Sudarshan Ananth , Lars Brink , Sucheta Majumdar

Using the method of maximal cuts, we obtain a form of the three-loop four-point scattering amplitude of N=8 supergravity in which all ultraviolet cancellations are made manifest. The Feynman loop integrals that appear have a graphical…

High Energy Physics - Theory · Physics 2009-11-13 Z. Bern , J. J. M. Carrasco , L. J. Dixon , H. Johansson , R. Roiban

We use the duality between color and kinematics to simplify the construction of the complete four-loop four-point amplitude of N=4 super-Yang-Mills theory, including the nonplanar contributions. The duality completely determines the…

High Energy Physics - Theory · Physics 2012-10-17 Z. Bern , J. J. M. Carrasco , L. J. Dixon , H. Johansson , R. Roiban

In four dimensions, it has long been established that gravity coupled to matter exhibits ultraviolet divergences at one loop, irrespective of supersymmetry. Notably, the four-matter one-loop amplitudes of half-maximal supergravity coupled…

High Energy Physics - Theory · Physics 2026-04-02 Yu-tin Huang , Henrik Johansson , Michele Santagata , Congkao Wen

The ultraviolet divergences of amplitude diagrams in maximal supergravity are investigated using the pure spinor superfield formalism in maximal supergravity, with maximally supersymmetric Yang-Mills theory for reference. We comment on the…

High Energy Physics - Theory · Physics 2015-08-18 Anna Karlsson

We present the complete four-loop four-point amplitude in N=4 super-Yang-Mills theory, for a general gauge group and general D-dimensional covariant kinematics, and including all non-planar contributions. We use the method of maximal cuts…

High Energy Physics - Theory · Physics 2011-03-03 Z. Bern , J. J. M. Carrasco , L. J. Dixon , H. Johansson , R. Roiban

We examine the ultraviolet behaviour of supergravity theories as a function of dimension and number of supercharges. We do so by the computation of one and two-loop physical on-shell four point amplitudes. For maximal supergravity, our…

High Energy Physics - Theory · Physics 2007-05-23 Z. Bern , D. Dunbar , L. Dixon , B. Julia , M. Perelstien , J. Rozowsky , D. Seminara , M. Trigante

The ultraviolet divergences of amplitude diagrams in maximal supergravity are characterised by a first possible divergence at seven loops for the 4-point amplitude (logarithmic) and, in its absence, at eight loops. We revisit the pure…

High Energy Physics - Theory · Physics 2015-08-18 Anna Karlsson
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