Continuing the investigation started in a previous work, we consider form factors of integrable quantum field theories in finite volume, extending our investigation to matrix elements with disconnected pieces. Numerical ...

Using the recently introduced boundary form factor bootstrap equations, the form factors of boundary exponential operators in the sinh-Gordon model are constructed. We also give a general method to evaluate the ultraviolet ...

We describe the volume dependence of matrix elements of local fields to all orders in inverse powers of the volume (i.e., only neglecting contributions that decay exponentially with volume). Using the scaling Lee-Yang model ...

A conjecture is presented for the thermal one-point function of boundary operators in integrable boundary quantum field theories in terms of form factors. It is expected to have applications in studying boundary critical ...

In this paper we consider excited state g-functions, that is, overlaps between boundary states and excited states in boundary conformal field theory. We find a new method to calculate these overlaps numerically using a ...

We analyze the evolution of the effective potential and the particle spectrum of two-parameter families of non-integrable quantum field theories. These theories are defined by deformations of conformal minimal models M-m ...

We compare form factors in sine-Gordon theory, obtained via the bootstrap, to finite volume matrix elements computed using the truncated conformal space approach. For breather form factors, this is essentially a straightforward ...

A previously conjectured set of exact form factors of boundary exponential operators in the sinh-Gordon model is tested against numerical results from boundary truncated conformal space approach in boundary sine-Gordon ...

We describe the volume dependence of matrix elements of local boundary fields to all orders in inverse powers of the volume. Using the scaling boundary Lee-Yang model as testing ground, we compare the matrix elements ...

Recently, the spectral expansion of finite temperature two-point functions in integrable quantum field theories was constructed using a finite volume regularization technique and the application of multidimensional residues. ...

We consider finite volume (or equivalently, finite temperature) expectation values of local operators in integrable quantum field theories using a combination of numerical and analytical approaches. It is shown that the ...

We consider the k-folded sine-Gordon model, obtained from the usual version by identifying the scalar field after k periods of the cosine potential. We examine (1) the ground state energy split, (2) the lowest lying ...

The two-frequency sine-Gordon model is examined. The focus is mainly on the case when the ratio of the frequencies is 1/2, given the recent interest in the literature. We discuss the model both in a perturbative (form ...

The sine-Gordon model with Neumann boundary condition is investigated. Using the bootstrap principle the spectrum of boundary bound states is established. Somewhat surprisingly it is found that Coleman-Thun diagrams and ...

We investigate the issues of unitarity and reality of the spectrum for the imaginary coupled affine Toda field theories based on a(1)((1)) and a(2)((2)) and the perturbed minimal models that arise from their various RSOS ...

The bound state spectrum and the associated reflection factors are determined for the sine-Gordon model with arbitrary integrable boundary condition by closing the bootstrap. Comparing the symmetries of the bound state ...

An asymptotic theory is developed for general non-integrable boundary quantum field theory in 1 + 1 dimensions based on the Lagrangian description. Reflection matrices are defined to connect asymptotic states and are ...

We examine the finite volume spectrum and boundary energy in boundary sine-Gordon theory, based on our recent results obtained by closing the boundary bootstrap. The spectrum and the reflection factors are checked against ...

We consider N = 1 supersymmetric sine-Gordon theory (SSG) with supersymmetric integrable boundary conditions (boundary SSG = BSSG). We find two possible ways to close the boundary bootstrap for this model, corresponding ...

The R-matrix of the U-q(d(4)((3))) algebra is constructed in the 8-dimensional fundamental representation. Using this result, an exact S-matrix is conjectured for the imaginary coupled g(2)((1)) affine Toda field theory, ...

Boundary form factor axioms are derived for the matrix elements of local boundary operators in integrable (1 + 1)-dimensional boundary quantum field theories using the analyticity properties of correlators; via the boundary ...

We develop methods to extract resonance widths from finite volume spectra of (1 + 1)-dimensional quantum field theories. Our two methods are based on Luscher's description of finite size corrections, and are dubbed the ...

We develop truncated conformal space (TCS) technique for perturbations of c = 1 conformal field theories. We use it to give the first numerical evidence of the validity of the non-linear integral equation (NLIE) derived ...

We consider quantum field theories with boundary on a codimension one hyperplane. Using 1+1 dimensional examples, we clarify the relation between three parameters characterizing one-point functions, finite size corrections ...

Boundary quantum field theory is investigated in the Lagrangian framework. Models are defined perturbatively around the Neumann boundary condition. The analyticity properties of the Green functions are analyzed: Landau ...

We examine the connection between the non-linear integral equation (NLIE) derived from light-cone lattice and sine-Gordon quantum field theory, considered as a perturbed c = 1 conformal field theory. After clarifying some ...

We consider SUSY sine-Gordon theory in the framework of perturbed conformal field theory. Using an argument from Zamolodchikov, we obtain the vacuum structure and the kink adjacency diagram of the theory, which is cross-checked ...

A non-linear integral equation (NLIE) governing the finite size effects of excited states of even topological charge in the sine-Gordon (sG) / massive Thirring (mTh) field theory, deducible from a light-cone lattice ...

Using the recently introduced boundary form factor bootstrap equations, we map the complete space of their solutions for the boundary version of the scaling Lee-Yang model and sinh-Gordon theory. We show that the complete ...

Using the reduced WZNW formulation we analyse the classical W-orbit content of the space of classical solutions of the A2 Toda theory. We define the quantized Toda field as a periodic primary field of the W-algebra satifying ...

There has been some debate about the validity of quantum affine Toda field theory at imaginary coupling, owing to the non-unitarity of the action, and consequently of its usefulness as a model of perturbed conformal field ...

Classical sine-Gordon theory on a strip with integrable boundary conditions is considered analyzing the static (ground state) solutions, their existence, energy and stability under small perturbations. The classical analogue ...

We describe an extension of the non-linear integral equation (NLIE) method to Virasoro minimal models perturbed by the relevant operator Phi((1,3)). Along the way, we also complete our previous studies of the finite volume ...

We derive a relation between leading finite size corrections for a (1 + 1)-dimensional quantum field theory on a strip and scattering data, which is very similar in spirit to the approach pioneered by Luscher for periodic ...

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 ...

The ground state energy of a boundary quantum field theory is derived in planar geometry in D + 1-dimensional spacetime. It provides a universal expression for the Casimir energy which exhibits its dependence on the boundary ...

We reconsider the mass spectrum of double sine-Gordon theory where recent semiclassical results called into question the previously accepted picture. We use the truncated conformal space approach (TCSA) to investigate the ...

We continue the investigation of massive integrable models by means of the bootstrap fusion procedure started in our previous work an the O(3) nonlinear sigma model. Using an analogy with the SU(2) Thirring model and the ...

The RSOS restriction of the Zhiber-Mikhailov-Shabat (ZMS) model is investigated. It is shown that in addition to the usual RSOS restriction, corresponding to Phi((1,2)) and Phi((2,1)) perturbations of minimal CFT, there ...

We consider the RSOS S-matrices of the Phi((1,5)) perturbed minimal models which have recently been found in a companion paper. These S-matrices have some interesting properties, in particular, unitarity may be broken in ...

An exact S-matrix is conjectured for the imaginary coupled d(4)((3)) affine Toda field theory, using the U-q(g(2)((1))) symmetry. It is shown that this S-matrix is consistent with the results for the case of real coupling ...