Search arXivSearch

arXiv · 0803.3999

Aspects of Integrability in AdS/CFT Duality

Abstract

In this dissertation, we discuss how our understanding of the large-N spectrum of AdS/CFT has been deepened by integrability-based approaches. We begin with a comprehensive review of the integrability of the gauge theory spin-chain and that of the string sigma model. In the light of the AdS/CFT duality, they should be just two ways of describing the same underlying integrability, and it is believed that the unified integrability can be characterised by a set of Bethe ansatz equations which is valid for all values of the 't Hooft coupling. By studying the asymptotic spectrum of the AdS/CFT in the infinite spin/R-charge limit, we first identify the corresponding solitonic counterparts in the context of the AdS/CFT, which are the so-called dyonic giant magnons and the SYM magnon boundstates. Then we show that the S-matrix computed directly from the string solitons scattering precisely reproduces the prediction from the conjecture. We further perform an analyticity test by studying the singularities of the conjectured magnon boundstate S-matrix and checking the physicality conditions. These tests give strong positive supports for the integrability of large-N AdS/CFT as well as the specific form of the conjectured Bethe ansatz equations. Concerning the string theory integrability, we also provide a detailed study of certain classical string solutions on AdS_5 x S^5. These are constructed in such a way they correspond to generic soliton solutions of (Complex) sine/sinh-Gordon equations via the so-called Pohlmeyer reduction procedure. Furthermore, we describe them in terms of algebro-geometric data as finite-gap solutions, giving a complete map of the elliptic string solutions.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Keisuke Okamura. 2008-04-07. Aspects of Integrability in AdS/CFT Duality. https://arxiv.org/abs/0803.3999

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Introduction to Generalized Symmetries

These notes were prepared for a series of intensive lectures delivered at Hokkaido University, Nagoya University, Kyoto University, and Kyushu University. We begin with a brief review of higher-form symmetries, anomalies, and discrete gauge theories, before introducing non-invertible symmetries in $(1+1)$-dimensional systems. The basic structure of fusion categories is then discussed, including a discussion of categorical analogs of discrete gauging and representation theory. We subsequently turn to $(3+1)$-dimensional theories, where several physical applications of non-invertible symmetries are discussed. These notes are intended to be largely self-contained, and require no prior familiarity with subjects such as conformal field theory or lattice models.

hep-th

Planar loop integrands from cuts in $D$ dimensions

We present a direct reconstruction formula for planar loop integrands from $D$-dimensional generalized unitarity cuts in any colored theory. The reconstruction combinatorics is separated from the theory-dependent tree amplitudes entering the cuts: for the $L$-loop $n$-point color-ordered amplitude, the integrand is expressed as a sum over admissible non-scaleless scalar graphs dressed by corresponding cuts in $D$ dimensions; the coefficients are given by the universal Möbius-inversion formula of the refinement poset, or equivalently one minus the Euler characteristics of associated complexes. As an application we write down closed-formulas for loop integrands in pure Yang--Mills theory, where the required cuts are generated by gluing $D$-dimensional tree amplitudes and summing over internal gluon states. We also use the two-loop five-point case as a validation, comparing with known integrand data and after integration-by-parts reduction, with known integrated helicity amplitudes. The same framework also produces compact cut-organized data for larger examples, including the two-loop six-point and three-loop four-point cases. We also describe the corresponding simplification in maximally supersymmetric Yang--Mills theory, where the absence of bubble and triangle subgraphs reduces the relevant cut poset substantially.

hep-th

Free Field Realization of $\mathcal{W}$-Algebra Associated with Exceptional Lie Algebras

We study the free field realization of the $\mathcal{W}$-algebra associated with the exceptional Lie algebras $E_6$, $E_7$, $E_8$, and $F_4$. We develop a recursive construction in which a $\mathcal{W}$-algebra of rank $r$ is obtained from a $\mathcal{W}$-algebra of rank $r-1$ together with a free boson. The $\mathcal{W}$-currents are constructed from the zero commutation relation with the screening charges. The $\mathcal{W}E_6/\mathcal{W}E_7$ algebra is constructed from the $\mathcal{W}D_5/\mathcal{W}D_6$ algebra and is shown to be the same as that realized from the $\mathcal{W}A_5/\mathcal{W}E_6$ algebra, up to a change of the free field basis. The spin-$8$ generator of the $\mathcal{W}E_8$ algebra is built from the $\mathcal{W}D_7$ algebra. The recursive construction of the $\mathcal{W}BC_r$ algebras is also studied. We then realize the $\mathcal{W}F_4$ algebra based on the $\mathcal{W}BC_3$ algebra. Furthermore, the $\mathcal{W}$-charges of the generators of the $\mathcal{W}E_{6,7}$, $\mathcal{W}BC_{2,3}$, and $\mathcal{W}F_4$ algebras are calculated and expressed in terms of the Casimir invariants.

hep-th