34 research outputs found
On the Moyal deformation of Nahm Equations in seven dimensions
We show how the reduced (anti-)self-dual Yang-Mills equations in seven
dimensions described by the Nahm equations can be carried over to the
Weyl-Wigner-Moyal formalism. In the process some new solutions for the cases of
gauge groups SU(2) and SL(2,R) are explicitly obtained.Comment: 16+1 pages, LaTeX, no figure
Ground-state Wigner functional of linearized gravitational field
The deformation quantization formalism is applied to the linearized
gravitational field. Standard aspects of this formalism are worked out before
the ground state Wigner functional is obtained. Finally, the propagator for the
graviton is also discussed within the context of this formalism.Comment: 18 pages, no figure
On the Reduced SU(N) Gauge Theory in the Weyl-Wigner-Moyal Formalism
Weyl-Wigner-Moyal formalism is used to describe the large- limit of
reduced SU quenching gauge theory. Moyal deformation of Schild-Eguchi
action is obtained.Comment: 24 pages, phyzzx file, no figures, version to appear in Int. J. Mod.
Phys.
Local Zeta Functions and KobaâNielsen String Amplitudes
This article is a survey of our recent work on the connections between KobaâNielsen amplitudes and local zeta functions (in the sense of Gelâfand, Weil, Igusa, Sato, Bernstein, Denef, Loeser, etc.). Our research program is motivated by the fact that the p-adic strings seem to be related in some interesting ways with ordinary strings. p-Adic string amplitudes share desired characteristics with their Archimedean counterparts, such as crossing symmetry and invariance under Möbius transformations. A direct connection between p-adic amplitudes and the Archimedean ones is through the limit pâ1. Gerasimov and Shatashvili studied the limit pâ1 of the p-adic effective action introduced by Brekke, Freund, Olson and Witten. They showed that this limit gives rise to a boundary string field theory, which was previously proposed by Witten in the context of background independent string theory. Explicit computations in the cases of 4 and 5 points show that the Feynman amplitudes at the tree level of the GerasimovâShatashvili Lagrangian are related to the limit pâ1 of the p-adic KobaâNielsen amplitudes. At a mathematical level, this phenomenon is deeply connected with the topological zeta functions introduced by Denef and Loeser. A KobaâNielsen amplitude is just a new type of local zeta function, which can be studied using embedded resolution of singularities. In this way, one shows the existence of a meromorphic continuations for the KobaâNielsen amplitudes as functions of the kinematic parameters. The KobaâNielsen local zeta functions are algebraic-geometric integrals that can be defined over arbitrary local fields (for instance R, C, Qp, Fp((T))), and it is completely natural to expect connections between these objects. The limit p tends to one of the KobaâNielsen amplitudes give rise to new amplitudes which we have called DenefâLoeser amplitudes. Throughout the article, we have emphasized the explicit calculations in the cases of 4 and 5 points
Link Invariants for Flows in Higher Dimensions
Linking numbers in higher dimensions and their generalization including gauge
fields are studied in the context of BF theories. The linking numbers
associated to -manifolds with smooth flows generated by divergence-free
p-vector fields, endowed with an invariant flow measure are computed in
different cases. They constitute invariants of smooth dynamical systems (for
non-singular flows) and generalizes previous results for the 3-dimensional
case. In particular, they generalizes to higher dimensions the Arnold's
asymptotic Hopf invariant for the three-dimensional case. This invariant is
generalized by a twisting with a non-abelian gauge connection. The computation
of the asymptotic Jones-Witten invariants for flows is naturally extended to
dimension n=2p+1. Finally we give a possible interpretation and implementation
of these issues in the context of string theory.Comment: 21+1 pages, LaTeX, no figure
Noncommutative Effects in the Black Hole Evaporation in Two Dimensions
We discuss some possible implications of a two-dimensional toy model for
black hole evaporation in noncommutative field theory. While the
noncommutativity we consider does not affect gravity, it can play an important
role in the dynamics of massless and Hermitian scalar fields in the event
horizon of a Schwarzschild black hole. We find that noncommutativity will
affect the flux of outgoing particles and the nature of its UV/IR divergences.
Moreover, we show that the noncommutative interaction does not affect Leahy's
and Unruh's interpretation of thermal ingoing and outgoing fluxes in the black
hole evaporation process. Thus, the noncommutative interaction still destroys
the thermal nature of fluxes. In the process, some nonlocal implications of the
noncommutativity are discussed.Comment: 33+1 pages, 3 eps figures, typos corrected, references added, figure
3 corrected, modifications in sections 4 and 6, version published in Phys.
Rev.
On the Deformation Quantization Description of Matrix Compactifications
Matrix theory compactifications on tori have associated Yang-Mills theories
on the dual tori with sixteen supercharges. A noncommutative description of
these Yang-Mills theories based in deformation quantization theory is provided.
We show that this framework allows a natural generalization of the `Moyal
B-deformation' of the Yang-Mills theories to non-constant background B-fields
on curved spaces. This generalization is described through Fedosov's geometry
of deformation quantization.Comment: 25 pages, harvmac file, no figures, corrected typos, added
references, one comment added in sec.
An Alternative Interpretation for the Moduli Fields of the Cosmology Associated to Type IIB Supergravity with Fluxes
We start with a particular cosmological model derived from type IIB
supergravity theory with fluxes, where usually the dilaton is interpreted as a
Quintessence field. Instead of that, in this letter we interpret the dilaton as
the dark matter of the universe. With this alternative interpretation we find
that in this supergravity model gives a similar evolution and structure
formation of the universe compared with the CDM model in the linear
regime of fluctuations of the structure formation. Some free parameters of the
theory are fixed using the present cosmological observations. In the non-linear
regimen there are some differences between the type IIB supergravity theory
with the traditional CDM paradigm. The supergravity theory predicts the
formation of galaxies earlier than the CDM and there is no density cusp in the
center of galaxies. These differences can distinguish both models and can give
a distinctive feature to the phenomenology of the cosmology coming from
superstring theory with fluxes.Comment: 7 pages, 5 figures, references added, minor modifications, typos
corrected. Version accepted for publication in IJMP