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9 papers found.
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On fine structure of strings: the universal correction to the Veneziano amplitude

Abstract We consider theories of weakly interacting higher spin particles in flat space-time. We focus on the four-point scattering amplitude at high energies and imaginary scattering angles. The leading asymptotic of the amplitude in this regime is universal and equal to the corresponding limit of the Veneziano amplitude. In this paper, we find tha the first sub-leading...

Large gauge symmetries and asymptotic states in QED

Large Gauge Transformations (LGT) are gauge transformations that do not vanish at infinity. Instead, they asymptotically approach arbitrary functions on the conformal sphere at infinity. Recently, it was argued that the LGT should be treated as an infinite set of global symmetries which are spontaneously broken by the vacuum. It was established that in QED, the Ward identities of...

OPE for all helicity amplitudes II. Form factors and data analysis

We present the general flux tube integrand for MHV and non-MHV amplitudes, in planar \( \mathcal{N}=4 \) SYM theory, up to a group theoretical rational factor. We find that the MHV and non-MHV cases only differ by simple form factors which we derive. This information allows us to run the operator product expansion program for all sorts of non-MHV amplitudes and to test the...

Adjoint BFKL at finite coupling: a short-cut from the collinear limit

In the high energy Regge limit, the six gluons scattering amplitude is controlled by the adjoint BFKL eigenvalue and impact factor. In this paper we determine these two building blocks at any value of the ’t Hooft coupling in planar \( \mathcal{N}=4 \) SYM theory. This is achieved by means of analytic continuations from the collinear limit, where similar all loops expressions...

OPE for all helicity amplitudes

We extend the Operator Product Expansion (OPE) for scattering amplitudes in planar \( \mathcal{N}=4 \) SYM to account for all possible helicities of the external states. This is done by constructing a simple map between helicity configurations and so-called charged pentagon transitions. These OPE building blocks are generalizations of the bosonic pentagons entering MHV amplitudes...

Space-time S-matrix and flux-tube S-matrix IV. Gluons and fusion

We analyze the pentagon transitions involving arbitrarily many flux-tube gluonic excitations and bound states thereof in planar \( \mathcal{N}=4 \) Super-Yang-Mills theory. We derive all-loop expressions for all these transitions by factorization and fusion of the elementary transitions for the lightest gluonic excitations conjectured in a previous paper. We apply the proposals...

Space-time S-matrix and flux-tube S-matrix III. The two-particle contributions

We consider light-like Wilson loops with hexagonal geometry in the planar limit of \( \mathcal{N} \) = 4 Super-Yang-Mills theory. Within the Operator-Product-Expansion framework these loops receive contributions from all states that can propagate on top of the colour flux tube sourced by any two opposite edges of the loops. Of particular interest are the two-particle...

Space-time S-matrix and flux tube S-matrix II. Extracting and matching data

We elaborate on a non-perturbative formulation of scattering amplitudes/null polygonal Wilson loops in planar \( \mathcal{N} \) = 4 Super-Yang-Mills theory. It allows one to compute a precise IR finite ratio of scattering amplitudes that captures all the conformally invariant data of interest. Our construction is based on a decomposition of the dual Wilson loops into elementary...