Bosonic sectorized strings and the (DF)2 theory

Ambitwistor strings are chiral (holomorphic) strings whose target is the space of complex null geodesics, ambitwistor space. We introduce twistor representations of ambitwistor space in 6 and 5 dimensions. In 6d the twistor representation is naturally conformally invariant. Anomaly cancellation leads to models that describe biadjoint scalar amplitudes and certain conformally invariant gauge and gravity theories, respectively of 4th and 6th order. There are three such models, reflecting triality for the conformal group SO(8) associated to these 6d models. On reduction to five dimensions, gauge anomaly cancellation requires supersymmetry and the resulting models describe maximally supersymmetric Yang-Mills and gravity. The twistor representation of these ambitwistor strings lead to formulæ for maximally supersymmetric gauge and gravity amplitudes based on the polarized scattering equations in 5d, found earlier by the first two authors.

Section: Discussionmentioning

confidence: 99%

“…Following the work of [26][27][28], the ambitwistor string correlator of states w gauge Φ k with standard polarization structure (3.18) are understood to correspond to amplitudes in the 4 th -order gauge theory with action…”

Section: Jhep08(2021)153mentioning

confidence: 99%

Ambitwistor strings in six and five dimensions

Geyer

Mason

Skinner

2021

“…Making this statement more precise will require a computation of the appropriate integrands coming from spin-1 and 2 vertex operators, which will be given in a future publication. Finally, it might be interesting to construct a version of our AdS model in the context of sectorized/chiral string [95][96][97][98][99][100], together with its intersection theory interpretation [65], which introduces a non-trivial α dependence to double-copy.…”

Section: Jhep11(2020)158mentioning

confidence: 99%

Scattering equations in AdS: scalar correlators in arbitrary dimensions

Eberhardt

Komatsu

Mizera

2020

We introduce a bosonic ambitwistor string theory in AdS space. Even though the theory is anomalous at the quantum level, one can nevertheless use it in the classical limit to derive a novel formula for correlation functions of boundary CFT operators in arbitrary space-time dimensions. The resulting construction can be treated as a natural extension of the CHY formalism for the flat-space S-matrix, as it similarly expresses tree-level amplitudes in AdS as integrals over the moduli space of Riemann spheres with punctures. These integrals localize on an operator-valued version of scattering equations, which we derive directly from the ambitwistor string action on a coset manifold. As a testing ground for this formalism we focus on the simplest case of ambitwistor string coupled to two cur- rent algebras, which gives bi-adjoint scalar correlators in AdS. In order to evaluate them directly, we make use of a series of contour deformations on the moduli space of punctured Riemann spheres and check that the result agrees with tree level Witten diagram computations to all multiplicity. We also initiate the study of eigenfunctions of scattering equations in AdS, which interpolate between conformal partial waves in different OPE channels, and point out a connection to an elliptic deformation of the Calogero-Sutherland model.

“…The formalism explicitly constructs tree amplitudes from the product of two half-integrands. There is now a well-developed program for exploring the types of objects needed in each half-integrand to generate theories of interest [27][28][29][30][31][32][33][34], which can be derived from world-sheet models based on ambitwistor strings [35][36][37][38][39] and their deformation [40,41]. The half-integrands are known to be expressible completely in Del Duca-Dixon-Maltoni half-ladder basis [42] on the support of scattering equations [26], 1…”

Section: Jhep12(2020)138mentioning

confidence: 99%

Efficient calculation of crossing symmetric BCJ tree numerators

Edison

Teng

2020

In this paper, we develop an improved method for directly calculating double-copy-compatible tree numerators in (super-)Yang-Mills and Yang-Mills-scalar theories. Our new scheme gets rid of any explicit dependence on reference orderings, restoring a form of crossing symmetry to the numerators. This in turn improves the computational efficiency of the algorithm, allowing us to go well beyond the number of external particles accessible with the reference order based methods. Motivated by a parallel study of one-loop BCJ numerators from forward limits, we explore the generalization to include a pair of fermions. To improve the accessibility of the new algorithm, we provide a Mathematica package that implements the numerator construction. The structure of the computation also provides for a straightforward introduction of minimally-coupled massive particles potentially useful for future computations in both classical and quantum gravity.