60 research outputs found
Covariant formulation of non-Abelian gauge theories without anticommuting variables
A manifestly Lorentz invariant effective action for Yang-Mills theory
depending only on commuting fields is constructed. This action posesses a
bosonic symmetry, which plays a role analogous to the BRST symmetry in the
standard formalism.Comment: 8 pages, Late
Hierarchy of massive gauge fields
An explicitely gauge invariant polynomial action for massive gauge fields is
proposed. For different values of parameters it describes massive Yang-Mills
field, the Higgs-Kibble model, the model with spontaneously broken symmetry and
two scalar mesons.Comment: 8 pages, no figure
Lattice QCD with Exponentially Small Chirality Breaking
A new multifermion formulation of lattice QCD is proposed. The model is free
of spectrum doubling and preserves all nonanomalous chiral symmetries up to
exponentially small corrections. It is argued that a small number of fermion
fields may provide a good approximation making computer simulations feasible.Comment: 14 pages, no figures; typos correcte
A practical gauge invariant regularization of the SO(10) grand unified model
It is shown that a simple modification of the dimensional regularization
allows to compute in a consistent and gauge invariant way any diagram with less
than four loops in the SO(10) unified model. The method applies also to the
Standard Model generated by the symmetry breaking . A gauge invariant regularization for arbitrary diagram is
also described.Comment: 10 pages, uses linedraw.st
Chiral symmetry in lattice QCD
A chiral invariant effective action for lattice QCD is proposed. Its
connection to the multifermion model is established. A possibility of using
this action for computer simulations is discussed.Comment: 3 pages, Lattice 2000(chiral fermions
QCD effective action with dressing functions - consistency checks in the perturbative regime
In a previous paper, we presented solution to the Slavnov--Taylor identity
for the QCD effective action, and argued that the action terms containing
(anti)ghost fields are unique. These terms have the same form as those in the
classical action, but the gluon and (anti)ghost effective fields are convoluted
with gluon and ghost dressing functions G_A and G_c, the latter containing
perturbative and nonperturbative effects (but not including the soliton-like
vacuum effects). In the present work we show how the perturbative QCD (pQCD)
can be incorporated into the framework of this action, and we present explicit
one-loop pQCD expressions for G_A and G_c. We then go on to check the
consistency of the obtained results by considering an antighost
Dyson--Schwinger equation (DSE). By solving the relations that result from the
Legendre transformation leading to the effective action, we obtain the
effective fields as power expansions of sources. We check explicitly that the
aforementioned one-loop functions G_A and G_c fulfil the antighost DSE at the
linear source level. We further explicitly check that these one-loop G_A and
G_c have the regularization-scale and momentum dependence consistent with the
antighost DSE at the quadratic source level. These checks suggest that the the
effective action with dressing functions represents a consistent framework for
treating QCD, at least at the one-loop level.Comment: 17 pages, revtex4; dimensional regularization used instead of
Pauli-Villars, the check of identity in the linear-in-sources Dyson-Schwinger
equation now includes the finite part; conclusions unchanged; to appear in
Phys.Rev.
Fermi-Bose duality via extra dimension
Representation of a -dimensional fermion determinant as a path integral of
exponent of a -dimensional Hermitean bosonic action is constructed.Comment: 7 pages, LATE
Bosonization of Fermion Determinants
A four dimensional fermion determinant is presented as a path integral of the
exponent of a local five dimensional action describing constrained bosonic
system. The construction is carried out both in the continuum theory and in the
lattice model.Comment: 9 pages, latex, no figure
An approach to solve Slavnov-Taylor identities in nonsupersymmetric non-Abelian gauge theories
We present a way to solve Slavnov--Taylor identities in a general
nonsupersymmetric theory. The solution can be parametrized by a limited number
of functions of spacetime coordinates, so that all the effective fields are
dressed by these functions via integral convolution. The solution restricts the
ghost part of the effective action and gives predictions for the physical part
of the effective action.Comment: revised version, section 3 is enlarged, 24 pages, Latex2e, no
figures, version accepted by Phys. Rev.
Generalized Pauli-Villars regularization for undoubled lattice fermions
A manifestly gauge invariant formulation of chiral theories with fermions on
the lattice is developed. It combines SLAC lattice derivative \cite{DWY},
\cite{ACS}, \cite{S} and generalized Pauli-Villars regularization \cite{FS}.
The theory is free of fermion doubling, requires only local gauge invariant
counterterms and produces correct results when applied to exactly solvable two
dimensional models.Comment: 10 pages LATEX fil
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