789 research outputs found
Spectral curve for gamma-deformed AdS/CFT
We construct the spectral curve of gamma-deformed AdS/CFT from the strong
coupling scaling limit of the T-system. As we interpret the twisted T-functions
in the classical limit as characters of the highest weight representations of
the psu(2,2|4) symmetry group, we compute the twisted quasimomenta which
characterize classical integrability and analyze their analytic and asymptotic
properties. These twisted quasimomenta are compared to Beisert-Roiban Bethe
ansatz equations and classical string solutions.Comment: 14 pages; v2 references added and typos correcte
Structure constants of operators on the Wilson loop from integrability
We study structure constants of local operators inserted on the Wilson loop
in super Yang-Mills theory. We compute the structure constants in
the SU(2) sector at tree level using the correspondence between operators on
the Wilson loop and the open spin chain. The results are interpreted as the
summation over all possible ways of changing the signs of magnon momenta in the
hexagon form factors. This is consistent with a holographic description of the
correlator as the cubic open string vertex, which consists of one hexagonal
patch and three boundaries. We then conjecture that a similar expression should
hold also at finite coupling.Comment: 38 pages; v3: JHEP published versio
Spectral curve for open strings attached to the Y=0 brane
The concept of spectral curve is generalized to open strings in AdS/CFT with
integrability preserving boundary conditions. Our definition is based on the
logarithms of the eigenvalues of the open monodromy matrix and makes possible
to determine all the analytic, symmetry and asymptotic properties of the
quasimomenta. We work out the details of the whole construction for the Y = 0
brane boundary condition. The quasimomenta of open circular strings are
explicitly calculated. We use the asymptotic solutions of the Y -system and the
boundary Bethe Ansatz equations to recover the spectral curve in the strong
coupling scaling limit. Using the curve the quasiclassical fluctuations of some
open string solutions are also studied.Comment: 34 pages, 2 figures; v3: typos corrected, sect.2.2 improve
Worldsheet S-matrix of beta-deformed SYM
We compute perturbative worldsheet S-matrix of beta-deformed AdS/CFT in the
strong and weak `t Hooft coupling limit to compare with exact S-matrix. For the
purpose we take near BMN limit of TsT-transformed AdS_5 x S^5 with the twisted
boundary condition and compute the S-matrix on worldsheet using light-cone
gauge fixed Lagrangian. For the weak coupling side, we compute the S-matrix in
the SU(3) sector by applying coordinate Bethe ansatz method to the one-loop
dilatation operator obtained from the deformed super Yang-Mills theory. These
analysis support the conjectured exact S-matrix in the leading order for both
sides of beta-deformed AdS/CFT along with appropriate twisted boundary
conditions.Comment: 12 page
Structure Constants of Defect Changing Operators on the 1/2 BPS Wilson Loop
We study three-point functions of operators on the BPS Wilson loop in
planar super Yang-Mills theory. The operators we consider are
"defect changing operators", which change the scalar coupled to the Wilson
loop. We first perform the computation at two loops in general set-ups, and
then study a special scaling limit called the ladders limit, in which the
spectrum is known to be described by a quantum mechanics with the
SL(2,) symmetry. In this limit, we resum the Feynman diagrams using
the Schwinger-Dyson equation and determine the structure constants at all order
in the rescaled coupling constant. Besides providing an interesting solvable
example of defect conformal field theories, our result gives invaluable data
for the integrability-based approach to the structure constants.Comment: 31 pages + appendices; v2 References adde
On integrable boundaries in the 2 dimensional -models
We make an attempt to map the integrable boundary conditions for 2
dimensional non-linear O(N) -models. We do it at various levels:
classically, by demanding the existence of infinitely many conserved local
charges and also by constructing the double row transfer matrix from the Lax
connection, which leads to the spectral curve formulation of the problem; at
the quantum level, we describe the solutions of the boundary Yang-Baxter
equation and derive the Bethe-Yang equations. We then show how to connect the
thermodynamic limit of the boundary Bethe-Yang equations to the spectral curve.Comment: Dedicated to the memory of Petr Kulish, 31 pages, 1 figure, v2:
conformality and integrability of the boundary conditions are distinguishe
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