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Related papers: Internal boundaries of the loop amplituhedron

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We establish that unitarity of scattering amplitudes imposes universal entropy bounds. The maximal entropy of a self-sustained quantum field object of radius R is equal to its surface area and at the same time to the inverse running…

High Energy Physics - Theory · Physics 2021-03-31 Gia Dvali

We study the maximally-helicity-violating (MHV) six-gluon scattering amplitude in planar $\mathcal{N} = 4$ super-Yang-Mills theory at finite coupling when all three cross ratios are small. It exhibits a double logarithmic scaling in the…

High Energy Physics - Theory · Physics 2020-04-29 Benjamin Basso , Lance J. Dixon , Georgios Papathanasiou

Superspace power-counting rules give estimates for the loop order at which divergences can first appear in non-renormalisable supersymmetric field theories. In some cases these estimates can be improved if harmonic superspace, rather than…

High Energy Physics - Theory · Physics 2010-04-05 P. S. Howe , K. S. Stelle

We review some recent additions to the tool-chest of techniques for finding compact integrand representations of multiloop gauge-theory amplitudes - including non-planar contributions - applicable for N=4 super-Yang-Mills in four and higher…

High Energy Physics - Theory · Physics 2015-05-27 John Joseph M. Carrasco , Henrik Johansson

Planar L-loop maximally helicity violating amplitudes in N = 4 supersymmetric Yang-Mills theory are believed to possess the remarkable property of satisfying iteration relations in L. We propose a simple new method for studying the…

High Energy Physics - Theory · Physics 2009-11-11 Freddy Cachazo , Marcus Spradlin , Anastasia Volovich

We derive novel recursion relations for all loop amplitude integrands of planar, maximally supersymmetric Yang-Mills theory in terms of unitarity-like `cuts' obtained via sequences of BCFW deformations in momentum-twistor space.

High Energy Physics - Theory · Physics 2023-05-04 Jacob L. Bourjaily , Simon Caron-Huot

We construct the complete (planar and non-planar) integrand for the six-loop four-point amplitude in maximal $D\le10$ super-Yang-Mills. This construction employs new advances that combat the proliferation of diagram contributions and state…

High Energy Physics - Theory · Physics 2021-12-13 John Joseph M. Carrasco , Alex Edison , Henrik Johansson

The infrared exponentiation properties of dimensionally-regularized multi-loop scattering amplitudes are typically hidden at the level of the integrand, materializing only after integral evaluation. We address this long-standing problem by…

High Energy Physics - Theory · Physics 2019-07-22 Robert M. Schabinger

We propose new formulae for the two-loop n-point D-dimensional integrands of scattering amplitudes in Yang-Mills theory and gravity. The loop integrands are written as a double-forward limit of tree-level trivalent diagrams, and are…

High Energy Physics - Theory · Physics 2020-01-29 Yvonne Geyer , Ricardo Monteiro , Ricardo Stark-Muchão

Let $k$ and $N$ be positive integers with $k\ge2$ even. In this paper we give general explicit upper-bounds in terms of $k$ and $N$ from which all the residual representations $\bar{\rho}_{f,\lambda}$ attached to non-CM newforms of weight…

Number Theory · Mathematics 2017-05-17 Nicolas Billerey , Luis V. Dieulefait

We compute the even part of the two-loop seven-point planar MHV amplitude in N=4 supersymmetric Yang-Mills theory. We find that the even part is expressed in terms of conformal integrals with simple rational coefficients. We also compute…

High Energy Physics - Theory · Physics 2009-06-30 C. Vergu

We give a representation of the parity-even part of the planar two-loop six-gluon MHV amplitude of N=4 super-Yang-Mills theory, in terms of loop-momentum integrals with simple dual conformal properties. We evaluate the integrals numerically…

High Energy Physics - Theory · Physics 2008-11-26 Z. Bern , L. J. Dixon , D. A. Kosower , R. Roiban , M. Spradlin , C. Vergu , A. Volovich

We propose a simple geometric algorithm for determining the complete set of branch points of amplitudes in planar N=4 super-Yang-Mills theory directly from the amplituhedron, without resorting to any particular representation in terms of…

High Energy Physics - Theory · Physics 2017-08-02 Tristan Dennen , Igor Prlina , Marcus Spradlin , Stefan Stanojevic , Anastasia Volovich

We compute the superconformal index of the $\mathcal{N}=4$ $SU(N)$ Yang-Mills theory through a residue calculation. The method is similar in spirit to the Bethe Ansatz formalism, except that all poles are explicitly known, and we do not…

High Energy Physics - Theory · Physics 2021-05-05 Kevin Goldstein , Vishnu Jejjala , Yang Lei , Sam van Leuven , Wei Li

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 investigate positivity properties in quantum field theory (QFT). We provide evidence,and in some case proofs, that many building blocks of scattering amplitudes, and in some cases the full amplitudes, satisfy an infinite number of…

High Energy Physics - Theory · Physics 2025-03-17 Johannes Henn , Prashanth Raman

We propose a first implementation of the integrand-reduction method for two-loop scattering amplitudes. We show that the residues of the amplitudes on multi-particle cuts are polynomials in the irreducible scalar products involving the loop…

High Energy Physics - Phenomenology · Physics 2015-05-30 Pierpaolo Mastrolia , Giovanni Ossola

We bootstrap the symbol of the maximal-helicity-violating four-particle form factor for the chiral part of the stress-tensor supermultiplet in planar $\mathcal{N}=4$ super-Yang-Mills theory at two loops. When minimally normalized, this…

High Energy Physics - Theory · Physics 2024-12-03 Lance J. Dixon , Ömer Gürdoğan , Yu-Ting Liu , Andrew J. McLeod , Matthias Wilhelm

We provide a simple analytic formula for the two-loop six-point ratio function of planar N = 4 super Yang-Mills theory. This result extends the analytic knowledge of multi-loop six-point amplitudes beyond those with maximal helicity…

High Energy Physics - Theory · Physics 2015-06-03 Lance J. Dixon , James M. Drummond , Johannes M. Henn

In this thesis, we study the all same helicity loop amplitudes in self-dual Yang-Mills and self-dual gravity. These amplitudes have long been conjectured to be interpreted as an anomaly and are recently linked to the UV divergence of…

High Energy Physics - Theory · Physics 2023-10-24 Pratik Chattopadhyay