9 research outputs found
Gauge-invariant massive BF models
Consistent interactions that can be added to a free, Abelian gauge theory
comprising a BF model and a finite set of massless real scalar fields are
constructed from the deformation of the solution to the master equation based
on specific cohomological techniques. Under the hypotheses of analyticity in
the coupling constant, Lorentz covariance, spacetime locality, Poincare
invariance, supplemented with the requirement on the preservation of the number
of derivatives on each field with respect to the free theory, we obtain that
the deformation procedure leads to two classes of gauge-invariant interacting
theories with a mass term for the BF vector field with U(1) gauge
invariance. In order to derive this result we have not used the Higgs mechanism
based on spontaneous symmetry breaking.Comment: 63 page
Yes-go cross-couplings in collections of tensor fields with mixed symmetries of the type (3,1) and (2,2)
Under the hypotheses of analyticity, locality, Lorentz covariance, and
Poincare invariance of the deformations, combined with the requirement that the
interaction vertices contain at most two space-time derivatives of the fields,
we investigate the consistent cross-couplings between two collections of tensor
fields with the mixed symmetries of the type (3,1) and (2,2). The computations
are done with the help of the deformation theory based on a cohomological
approach in the context of the antifield-BRST formalism. Our results can be
synthesized in: 1. there appear consistent cross-couplings between the two
types of field collections at order one and two in the coupling constant such
that some of the gauge generators and of the reducibility functions are
deformed, and 2. the existence or not of cross-couplings among different fields
with the mixed symmetry of the Riemann tensor depends on the indefinite or
respectively positive-definite behaviour of the quadratic form defined by the
kinetic terms from the free Lagrangian.Comment: 35 page
Cohomological BRST aspects of the massless tensor field with the mixed symmetry (k,k)
The main BRST cohomological properties of a free, massless tensor field that
transforms in an irreducible representation of GL(D,R), corresponding to a
rectangular, two-column Young diagram with k>2 rows are studied in detail. In
particular, it is shown that any non-trivial co-cycle from the local BRST
cohomology group H(s|d) can be taken to stop either at antighost number (k+1)
or k, its last component belonging to the cohomology of the exterior
longitudinal derivative H(gamma) and containing non-trivial elements from the
(invariant) characteristic cohomology H^{inv}(delta|d).Comment: Latex, 50 pages, uses amssym
Hamiltonian BRST deformation of a class of n-dimensional BF-type theories
Consistent Hamiltonian interactions that can be added to an abelian free
BF-type class of theories in any n greater or equal to 4 spacetime dimensions
are constructed in the framework of the Hamiltonian BRST deformation based on
cohomological techniques. The resulting model is an interacting field theory in
higher dimensions with an open algebra of on-shell reducible first-class
constraints. We argue that the Hamiltonian couplings are related to a natural
structure of Poisson manifold on the target space.Comment: 27 pages, uses JHEP3.cl
On the generalized Freedman-Townsend model
Consistent interactions that can be added to a free, Abelian gauge theory
comprising a finite collection of BF models and a finite set of two-form gauge
fields (with the Lagrangian action written in first-order form as a sum of
Abelian Freedman-Townsend models) are constructed from the deformation of the
solution to the master equation based on specific cohomological techniques.
Under the hypotheses of smoothness in the coupling constant, locality, Lorentz
covariance, and Poincare invariance of the interactions, supplemented with the
requirement on the preservation of the number of derivatives on each field with
respect to the free theory, we obtain that the deformation procedure modifies
the Lagrangian action, the gauge transformations as well as the accompanying
algebra. The interacting Lagrangian action contains a generalized version of
non-Abelian Freedman-Townsend model. The consistency of interactions to all
orders in the coupling constant unfolds certain equations, which are shown to
have solutions.Comment: LaTeX, 62 page
Consistent Deformations for a Non-Standard <i>D</i> = 6 Topological BF Model from a BRST-Symmetry-Based Cohomological Approach
This paper falls under the heading of constructing consistent self-couplings in topological BF models. Our endeavor is of interest in the context of pure gravity, General Relativity, and super-gravity in Ashtekar formalism, which allow for certain economic formulations in terms of self-coupled BF theories in the presence of certain extra-constraints. More precisely, herein we address the construction of a special class of D=6 self-interactions for a collection of topological BF models with a non-standard field spectrum. Our methodology relies on a deformation method based on the relationship between antifield–BRST symmetry and the non-trivial gauge symmetries of a given field theory and implemented via the computation of certain precise spaces of the local BRST cohomology corresponding to the free limit. This cohomological BRST approach is applied to the starting free model under standard “selection rules” from Quantum Field Theory. Our findings are completely new and reveal a self-interacting topological BF model in D=6 with a complex gauge structure that is entirely read from the expression of the fully deformed solution to the classical master equation (the canonical generator of the antifield–BRST symmetry), and includes a generalization of the famous D=2 gravity in BF formulation
Consistent Deformations for a Non-Standard D = 6 Topological BF Model from a BRST-Symmetry-Based Cohomological Approach
This paper falls under the heading of constructing consistent self-couplings in topological BF models. Our endeavor is of interest in the context of pure gravity, General Relativity, and super-gravity in Ashtekar formalism, which allow for certain economic formulations in terms of self-coupled BF theories in the presence of certain extra-constraints. More precisely, herein we address the construction of a special class of D=6 self-interactions for a collection of topological BF models with a non-standard field spectrum. Our methodology relies on a deformation method based on the relationship between antifield–BRST symmetry and the non-trivial gauge symmetries of a given field theory and implemented via the computation of certain precise spaces of the local BRST cohomology corresponding to the free limit. This cohomological BRST approach is applied to the starting free model under standard “selection rules” from Quantum Field Theory. Our findings are completely new and reveal a self-interacting topological BF model in D=6 with a complex gauge structure that is entirely read from the expression of the fully deformed solution to the classical master equation (the canonical generator of the antifield–BRST symmetry), and includes a generalization of the famous D=2 gravity in BF formulation