Non-local Thirring model at finite-temperature

We extend a recently proposed non-local and non-covariant version of the Thirring model to the finite-temperature case. We obtain a completely bosonized expression for the partition function, describing the thermodynamics of the collective modes which are the underlying excitations of this system. From this result we derive closed formulae for the free-energy, specific-heat, two-point correlation functions and momentum distribution, as functionals of electron-electron coupling potentials.Comment: 23 pages, latex, no figure

Field theoretical approach to non-local interactions: 1d electrons and fermionic impurities

We apply a recently proposed path-integral approach to non-local bosonization to a Thirring-like system modeling non-relativistic massless particles interacting with localized fermionic impurities. We consider forward scattering processes described by symmetric potentials including interactions between charge, current, spin and spin-current densities. In the general (spin-flipping) problem we obtain an effective action for the collective modes of the model at T = 0, containing WZW-type terms. When spin-flipping processes are disregarded the structure of the action is considerably simplified, allowing us to derive exact expressions for the dispersion relations of collective modes and two point fermionic correlation functions as functionals of the potentials. Finally, as an example, we compute the momentum distribution for the case in which electrons and impurities are coupled through spin and spin-current densities only. The formulae we get suggest that our formalism could be useful in order to seek for a mechanism able to restore Fermi liquid behavior.Comment: 27 pages, Latex file, no figure

Path-Integral bosonization of a non-local interaction and its application to the study of 1-d many-body systems

We extend the path-integral approach to bosonization to the case in which the fermionic interaction is non-local. In particular we obtain a completely bosonized version of a Thirring-like model with currents coupled by general (symmetric) bilocal potentials. The model contains the Tomonaga-Luttinger model as a special case; exploiting this fact we study the basic properties of the 1-d spinless fermionic gas: fermionic correlators, the spectrum of collective modes, etc. Finally we discuss the generalization of our procedure to the non-Abelian case, thus providing a new tool to be used in the study of 1-d many-body systems with spin-flipping interactions.Comment: 26 pages LATEX, La Plata 94-0

Fermion Condensates of massless QED2QED_2 at Finite Density in non-trivial Topological Sectors

Vacuum expectation values of products of local bilinears $\bar\psi\psi$ are computed in massless $QED_2$ at finite density. It is shown that chiral condensates exhibit an oscillatory inhomogeneous behaviour depending on the chemical potential. The use of a path-integral approach clarifies the connection of this phenomenon with the topological structure of the theory.Comment: 16 pages, no figures, To be published in Phys.Rev.