1,073 research outputs found
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
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
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
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.
Faddeev-Jackiw Analysis of Topological Mass Generating Action
We analyze the gauge symmetry of a topological mass generating action in four
dimensions which contains both a vector and a second rank antisymmetric tensor
fields. In the Abelian case, this system induces an effective mass for the
vector gauge field via a topological coupling in the presence of a
kinetic term for the antisymmetric tensor field , while maintaining a gauge
symmetry. On the other hand, for the non-Abelian case the field does not
have a gauge symmetry unless an auxiliary vector field is introduced to the
system. We analyze this change of symmetry in the Faddeev-Jackiw formalism, and
show how the auxiliary vector field enhances the symmetry. At the same time
this enhanced gauge symmetry becomes reducible. We also show this phenomenon in
this analysis.Comment: 20 pages, REVTe
Effective Actions for 0+1 Dimensional Scalar QED and its SUSY Generalization at
We compute the effective actions for the 0+1 dimensional scalar field
interacting with an Abelian gauge background, as well as for its supersymmetric
generalization at finite temperature.Comment: 5 pages, Latex fil
Heterogeneity of left ventricular perfusion during pulmonary edema and microembolism treated with positive end-expiratory pressure and norepinephrine
New forms of BRST symmetry in rigid rotor
We derive the different forms of BRST symmetry by using the
Batalin-Fradkin-Vilkovisky formalism in a rigid rotor. The so called
"dual-BRST" symmetry is obtained from usual BRST symmetry by making a canonical
transformation in the ghost sector. On the other hand, a canonical
transformation in the sector involving Lagrange multiplier and its
corresponding momentum leads to a new form of BRST as well as dual-BRST
symmetry.Comment: 10 Pages, revtex, No Fig
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