We present a unified approach to the Thermodynamic Bethe Ansatz (TBA) for magnetic chains and field theories that includes the finite size (and zero temperature) calculations for lattice BA models.… (More)

Progress on string theory in curved spacetimes since 1992 are reviewed. After a short introduction on strings in Minkowski and curved spacetimes, we focus on strings in cosmological spacetimes. The… (More)

We show that the self-gravitating gas at thermal equilibrium has an infinite volume limit in the three ensembles (GCE, CE, MCE) when (N, V ) → ∞, keeping N/V 1/3 fixed, that is, with η ≡ G mN V 1/3 T… (More)

Boundary K-matrices for the six vertex and the n(2n − 1) A n−1 vertex models Abstract Boundary conditions compatible with integrability are obtained for two dimensional models by solving the… (More)

The general solutions for the factorization equations of the reflection matrices K ± (θ) for the eight vertex and six vertex models (XYZ, XXZ and XXX chains) are found. The associated integrable… (More)

While the universe becomes more and more homogeneous at large scales, statistical analysis of galaxy catalogs have revealed a fractal structure at small-scales (λ < 100h−1 Mpc), with a fractal… (More)

D. Boyanovsky, H.J. de Vega, R. Holman and J. F. J. Salgado (a) Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, PA. 15260, U.S.A. (b) LPTHE, ∗ Université Pierre et Marie… (More)

We consider the case of a scalar field, the inflaton, coupled to both lighter scalars and fermions, and the study the relaxation of the inflaton via particle production in both the linear and… (More)

The exact general evolution of circular strings in 2 + 1 dimensional de Sitter spacetime is described closely and completely in terms of elliptic functions. The evolution depends on a constant… (More)