v 1 3 0 N ov 1 99 2 SISSA 192 / 92 / EP S - Matrices of φ 1 , 2 perturbed unitary minimal models : IRF - Formulation and Bootstrap - Program

X iv : h ep - t h / 92 11 01 0 v 1 2 N ov 1 99 2 SISSA - EP - 154 RG flows and resonance scattering amplitudes ∗ Márcio

We review recent progresses in the study of factorized resonance scattering Smatrices. The resonance amplitudes are introduced through a suitable analytical continuation of the ADE Toda S-matrices. By using the thermodynamic Bethe ansatz approach we are able to compute the ground state energy, which describes a rich pattern of flows interpolating between the central charges of the coset models ...

ar X iv : h ep - p h / 92 11 23 8 v 1 1 1 N ov 1 99 2 Properties of perturbative multi - particle amplitudes in φ k and O ( N ) theories

ar X iv : h ep - t h / 92 04 08 6 v 1 2 7 A pr 1 99 2 19 / 92 March 1992 Quantum Group σ Models

Field-theoretic models for fields taking values in quantum groups are investigated. First we consider SU q (2) σ model (q real) expressed in terms of basic notions of noncommutative differential geometry. We discuss the case in which the σ models fields are represented as products of conventional σ fields and of the coordinate-independent algebra. An explicit example is provided by the U q (2) ...

ar X iv : h ep - p h / 92 11 22 0 v 1 6 N ov 1 99 2 Critical Temperature for the λ ( φ 4 ) 4 Within the δ - Expansion

We apply the δ-expansion perturbation scheme to the λφ4 self-interacting scalar field theory in 3+1 D at finite temperature. In the δ-expansion the interaction term is written as λ(φ2)1+δ and δ is considered as the perturbation parameter. We compute, in this perturbation approach, the renormalized mass at finite temperature from which we get the critical temperature. The results are compared wi...

On the relation between Φ ( 1 , 2 ) and Φ ( 1 , 5 ) perturbed minimal models and unitarity

We consider the RSOS S–matrices of the Φ(1,5) perturbed minimal models which have recently been found in the companion paper [1]. These S–matrices have some interesting properties, in particular, unitarity may be broken in a stronger sense than seen before, while one of the three classes of Φ(1,5) perturbations (to be described) shares the same Thermodynamic Bethe Ansatz as a related Φ(1,2) per...