Boundary finite size corrections for multiparticle states and planar AdS/CFT

We propose formulas for the L\"uscher type finite size energy correction of multiparticle states on the interval and evaluate them for the simplest case in the AdS/CFT setting. By this we determine the leading wrapping correction to the anomalous dimension of the simplest determinant type operator, which corresponds to a one particle state on the Y=0 brane.Comment: 21 pages, 22 eps figures, v2: references added, v3: typos, fermionic signs are corrected in section 4, explicit results simplified, conclusion is unchange

Defect scaling Lee-Yang model from the perturbed DCFT point of view

We analyze the defect scaling Lee-Yang model from the perturbed defect conformal field theory (DCFT) point of view. First the defect Lee-Yang model is solved by calculating its structure constants from the sewing relations. Integrable defect perturbations are identified in conformal defect perturbation theory. Then pure defect flows connecting integrable conformal defects are described. We develop a defect truncated conformal space approach (DTCSA) to analyze the one parameter family of integrable massive perturbations in finite volume numerically. Fusing the integrable defect to an integrable boundary the relation between the IR and UV parameters can be derived from the boundary relations. We checked these results by comparing the spectrum for large volumes to the scattering theory.Comment: LaTeX, 33 pages, 9 figures, figures adde

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

On integrable boundaries in the 2 dimensional O(N)O(N) σ\sigma-models

We make an attempt to map the integrable boundary conditions for 2 dimensional non-linear O(N) $\sigma$-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

NLIE for hole excited states in the sine-Gordon model with two boundaries

We derive a nonlinear integral equation (NLIE) for some bulk excited states of the sine-Gordon model on a finite interval with general integrable boundary interactions, including boundary terms proportional to the first time derivative of the field. We use this NLIE to compute numerically the dimensions of these states as a function of scale, and check the UV and IR limits analytically. We also find further support for the ground-state NLIE by comparison with boundary conformal perturbation theory (BCPT), boundary truncated conformal space approach (BTCSA) and the boundary analogue of the Luscher formula.Comment: 31 pages, LaTeX; graphicx, epstopdf, 4 figure