On the trace anomaly and the energy-momentum conservation of quantum fields at D=2 in classical curved backgrounds

We study the conformal symmetry and the energy-momentum conservation of scalar field interacting with a curved background at D=2. We avoid to incorporate the metric determinant into the measure of the scalar field to explain the conformal anomaly and the consequent energy-momentum conservation. Contrarily, we split the scalar field in two other fields, in such a way that just one of them can be quantized. We show that the same usual geometric quantities of the anomaly are obtained, which are accompanied by terms containing the new field of the theory.Comment: 5 pages, no figure

Time-dependent cosmological constant in the Jackiw-Teitelboim cosmology

We study the obtainment of a time-dependent cosmological constant at D=2 in a model based on the Jackiw-Teitelboim cosmology. We show that the cosmological term goes to zero asymptotically and can induce a nonsingular behavior at the origin.Comment: 4 pages, Revtex4, twocolum

Symplectic Quantization for Reducible Systems

We study an extension of the symplectic formalism in order to quantize reducible systems. We show that a procedure like {\it ghost-of-ghost} of the BFV method can be applied in terms of Lagrange multipliers. We use the developed formalism to quantize the antisymmetric Abelian gauge fields.Comment: 12 pages, IF-UFRJ-22/9

The effect of different regulators in the non-local field-antifield quantization

Recently it was shown how to regularize the Batalin-Vilkovisky (BV) field-antifield formalism of quantization of gauge theories with the non-local regularization (NLR) method. The objective of this work is to make an analysis of the behaviour of this NLR formalism, connected to the BV framework, using two different regulators: a simple second order differential regulator and a Fujikawa-like regulator. This analysis has been made in the light of the well known fact that different regulators can generate different expressions for anomalies that are related by a local couterterm, or that are equivalent after a reparametrization. This has been done by computing precisely the anomaly of the chiral Schwinger model.Comment: 9 pages, Revtex. To appear in Int. J. Mod. Phys.