TY - JOUR

T1 - Twisting perturbed parafermions

AU - Belitsky, Andrei

N1 - Funding Information:
We would like to thank Ivan Kostov, Valya Petkova and Arkady Tseytlin for insightful communications. A part of this work was done while the author was visiting Universita di Bologna and he would like to thank Alfredo Bonini, Davide Fioravanti, Simone Piscaglia, Francesco Ravanini and Marco Rossi for warm hospitality and numerous discussions. This research was supported by the U.S. National Science Foundation under the grant PHY-1403891.

PY - 2017/7/10

Y1 - 2017/7/10

N2 - The near-collinear expansion of scattering amplitudes in maximally supersymmetric Yang–Mills theory at strong coupling is governed by the dynamics of stings propagating on the five sphere. The pentagon transitions in the operator product expansion which systematize the series get reformulated in terms of matrix elements of branch-point twist operators in the two-dimensional O(6) nonlinear sigma model. The facts that the latter is an asymptotically free field theory and that there exists no local realization of twist fields prevents one from explicit calculation of their scaling dimensions and operator product expansion coefficients. This complication is bypassed making use of the equivalence of the sigma model to the infinite-level limit of WZNW models perturbed by current–current interactions, such that one can use conformal symmetry and conformal perturbation theory for systematic calculations. Presently, to set up the formalism, we consider the O(3) sigma model which is reformulated as perturbed parafermions.

AB - The near-collinear expansion of scattering amplitudes in maximally supersymmetric Yang–Mills theory at strong coupling is governed by the dynamics of stings propagating on the five sphere. The pentagon transitions in the operator product expansion which systematize the series get reformulated in terms of matrix elements of branch-point twist operators in the two-dimensional O(6) nonlinear sigma model. The facts that the latter is an asymptotically free field theory and that there exists no local realization of twist fields prevents one from explicit calculation of their scaling dimensions and operator product expansion coefficients. This complication is bypassed making use of the equivalence of the sigma model to the infinite-level limit of WZNW models perturbed by current–current interactions, such that one can use conformal symmetry and conformal perturbation theory for systematic calculations. Presently, to set up the formalism, we consider the O(3) sigma model which is reformulated as perturbed parafermions.

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U2 - 10.1016/j.physletb.2017.04.038

DO - 10.1016/j.physletb.2017.04.038

M3 - Article

AN - SCOPUS:85018788222

VL - 770

SP - 35

EP - 42

JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

SN - 0370-2693

ER -