47 research outputs found
On presymplectic structures for massless higher-spin fields
A natural presymplectic structure for non-Lagrangian equations of motion
governing the dynamics of free higher-spin fields in four-dimensional anti-de
Sitter space is proposed. This presymplectic structure is then used to the
derivation of the conserved currents associated with the relativistic
invariance and to the construction of local functionals of fields that are
gauge invariant on shell.Comment: 28 pages; V2 - a section on weak Lagrangians and some references
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Variational tricomplex of a local gauge system, Lagrange structure and weak Poisson bracket
We introduce the concept of a variational tricomplex, which is applicable
both to variational and non-variational gauge systems. Assigning this
tricomplex with an appropriate symplectic structure and a Cauchy foliation, we
establish a general correspondence between the Lagrangian and Hamiltonian
pictures of one and the same (not necessarily variational) dynamics. In
practical terms, this correspondence allows one to construct the generating
functional of weak Poisson structure starting from that of Lagrange structure.
As a byproduct, a covariant procedure is proposed for deriving the classical
BRST charge of the BFV formalism by a given BV master action. The general
approach is illustrated by the examples of Maxwell's electrodynamics and chiral
bosons in two dimensions.Comment: 34 pages, v2 minor correction
Lifting a Weak Poisson Bracket to the Algebra of Forms
We detail the construction of a weak Poisson bracket over a submanifold of a
smooth manifold M with respect to a local foliation of this submanifold. Such a
bracket satisfies a weak type Jacobi identity but may be viewed as a usual
Poisson bracket on the space of leaves of the foliation. We then lift this weak
Poisson bracket to a weak odd Poisson bracket on the odd tangent bundle,
interpreted as a weak Koszul bracket on differential forms on M. This lift is
achieved by encoding the weak Poisson structure into a homotopy Poisson
structure on an extended manifold, and lifting the Hamiltonian function that
generates this structure. Such a construction has direct physical
interpretation. For a generic gauge system, the submanifold may be viewed as a
stationary surface or a constraint surface, with the foliation given by the
foliation of the gauge orbits. Through this interpretation, the lift of the
weak Poisson structure is simply a lift of the action generating the
corresponding BRST operator of the system
Cup product on A∞-cohomology and deformations
We propose a simple method for constructing formal deformations of differential graded algebras in the category of minimal A∞-algebras. The basis for our approach is provided by the Gerstenhaber algebra structure on A∞-cohomology, which we define in terms of the brace operations. As an example, we construct a minimal A∞-algebra from the Weyl–Moyal ∗-product algebra of polynomial functions
Lagrange Anchor and Characteristic Symmetries of Free Massless Fields
A Poincar\'e covariant Lagrange anchor is found for the non-Lagrangian
relativistic wave equations of Bargmann and Wigner describing free massless
fields of spin in four-dimensional Minkowski space. By making use of
this Lagrange anchor, we assign a symmetry to each conservation law and perform
the path-integral quantization of the theory
Slightly broken higher spin symmetry: general structure of correlators
We explore a class of CFT’s with higher spin currents and charges. Away from the free or N = ∞ limit the non-conservation of currents is governed by operators built out of the currents themselves, which deforms the algebra of charges by, and together with, its action on the currents. This structure is encoded in a certain A∞/L∞-algebra. Under quite general assumptions we construct invariants of the deformed higher spin symmetry, which are candidate correlation functions. In particular, we show that there is a finite number of independent structures at the n-point level. The invariants are found to have a form reminiscent of a one-loop exact theory. In the case of Chern-Simons vector models the uniqueness of the invariants implies the three-dimensional bosonization duality in the large-N limit