418 research outputs found
Estimativa de custo de produção de trigo, no sistema plantio direto, safra 2000.
bitstream/item/24902/1/COT200013.pd
New Results on N=4 SuperYang-Mills Theory
The N=4 SuperYang--Mills theory is covariantly determined by a U(1) \times
SU(2) \subset SL(2,R) \times SU(2) internal symmetry and two scalar and one
vector BRST topological symmetry operators. This determines an off-shell closed
sector of N=4 SuperYang-Mills, with 6 generators, which is big enough to fully
determine the theory, in a Lorentz covariant way. This reduced algebra derives
from horizontality conditions in four dimensions. The horizontality conditions
only depend on the geometry of the Yang-Mills fields. They also descend from a
genuine horizontality condition in eight dimensions. In fact, the SL(2,R)
symmetry is induced by a dimensional reduction from eight to seven dimensions,
which establishes a ghost-antighost symmetry, while the SU(2) symmetry occurs
by dimensional reduction from seven to four dimensions. When the four
dimensional manifold is hyperKahler, one can perform a twist operation that
defines the N=4 supersymmetry and its SL(2,H)\sim SU(4) R-symmetry in flat
space. (For defining a TQFT on a more general four manifold, one can use the
internal SU(2)-symmetry and redefine a Lorentz SO(4) invariance). These results
extend in a covariant way the light cone property that the N=4 SuperYang-Mills
theory is actually determined by only 8 independent generators, instead of the
16 generators that occur in the physical representation of the superPoincare
algebra. The topological construction disentangles the off-shell closed sector
of the (twisted) maximally supersymmetric theory from the (irrelevant) sector
that closes only modulo equations of motion. It allows one to escape the
question of auxiliary fields in N=4 SuperYang-Mills theory.Comment: 14 page
Estimativa de custo de produção de arroz de sequeiro, safra 2000/2001, em Mato Grosso.
bitstream/item/65586/1/Cot20-2000.pd
Estimativa de custo de produção de soja, safra 2000/2001, em Mato Grosso do Sul.
bitstream/item/24901/1/COT200014.pd
Estimativa de custo de produção de algodão, safra 2000/2001, em Mato Grosso do Sul.
bitstream/item/25003/1/COT200016.pd
A remark on the BRST symmetry in the Gribov-Zwanziger theory
We show that the soft breaking of the BRST symmetry arising in the
Gribov-Zwanziger theory can be converted into a linear breaking upon
introduction of a set of BRST quartets of auxiliary fields. Due to its
compatibility with the Quantum Action Principle, the linearly broken BRST
symmetry can be directly converted into a suitable set of useful Slavnov-Taylor
identities. As a consequence, it turns out that the renormalization aspects of
the Gribov-Zwanziger theory can be addressed by means of the cohomology of a
nilpotent local operatorComment: 11 pages, final version to appear in Phys. Rev.
Renormalizability of the linearly broken formulation of the BRST symmetry in presence of the Gribov horizon in Landau gauge Euclidean Yang-Mills theories
In previous work arXiv:1009.4135 we have shown that the soft breaking of the
BRST symmetry arising within the Gribov-Zwanziger framework can be converted
into a linear breaking, while preserving the nilpotency of the BRST operator.
Due to its compatibility with the Quantum Action Principle, the linearly broken
BRST symmetry directly translates into a set of Slavnov-Taylor identities. We
show that these identities guarantee the multiplicative renormalizability of
both Gribov-Zwanziger and Refined Gribov-Zwanziger theories to all orders. The
known property that only two renormalization factors are needed is recovered.
The non-renormalization theorem of the gluon-ghost-antighost vertex as well as
the renormalization factor of the Gribov parameter are derived within the
linearly broken formulation.Comment: 20 pages, references added, version accepted for publication in
Physical Review
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