51,968 research outputs found
Non-Associativity in the Clifford Bundle on the Parallelizable Torsion 7-Sphere
In this paper we discuss generalized properties of non-associativity in
Clifford bundles on the 7-sphere S7. Novel and prominent properties inherited
from the non-associative structure of the Clifford bundle on S7 are
demonstrated. They naturally lead to general transformations of the spinor
fields on S7 and have dramatic consequences for the associated Kac-Moody
current algebras. All additional properties concerning the non-associative
structure in the Clifford bundle on S7 are considered. We further discuss and
explore their applications.Comment: 16 page
Black hole acoustics in the minimal geometric deformation of a de Laval nozzle
The correspondence between sound waves, in a de Laval propelling nozzle, and
quasinormal modes emitted by brane-world black holes deformed by a 5D bulk Weyl
fluid are here explored and scrutinised. The analysis of sound waves patterns
in a de Laval nozzle at a laboratory, reciprocally, is here shown to provide
relevant data about the 5D bulk Weyl fluid and its on-brane projection,
comprised by the minimal geometrically deformed compact stellar distribution on
the brane. Acoustic perturbations of the gas fluid flow in the de Laval nozzle
are proved to coincide to the quasinormal modes of black holes solutions
deformed by the 5D Weyl fluid, in the geometric deformation procedure. Hence,
in a phenomenological E\"otv\"os-Friedmann fluid brane-world model, the
realistic shape of a de Laval nozzle is derived and its consequences studied.Comment: 7 pages, 3 figure
On Clifford Subalgebras, Spacetime Splittings and Applications
Z2-gradings of Clifford algebras are reviewed and we shall be concerned with
an alpha-grading based on the structure of inner automorphisms, which is
closely related to the spacetime splitting, if we consider the standard
conjugation map automorphism by an arbitrary, but fixed, splitting vector.
After briefly sketching the orthogonal and parallel components of products of
differential forms, where we introduce the parallel [orthogonal] part as the
space [time] component, we provide a detailed exposition of the Dirac operator
splitting and we show how the differential operator parallel and orthogonal
components are related to the Lie derivative along the splitting vector and the
angular momentum splitting bivector. We also introduce multivectorial-induced
alpha-gradings and present the Dirac equation in terms of the spacetime
splitting, where the Dirac spinor field is shown to be a direct sum of two
quaternions. We point out some possible physical applications of the formalism
developed.Comment: 22 pages, accepted for publication in International Journal of
Geometric Methods in Modern Physics 3 (8) (2006
Dynamical dispersion relation for ELKO dark spinor fields
An intrinsic mass generation mechanism for exotic ELKO dark matter fields is
scrutinized, in the context of the very special relativity (VSR). Our results
are reported on unraveling inequivalent spin structures that educe an
additional term on the associated Dirac operator. Contrary to the spinor fields
of mass dimension 3/2, this term is precluded to be absorbed as a shift of some
gauge vector potential, regarding the equations for the dark spinor fields. It
leads to some dynamical constraints that can be intrinsically converted into a
dark spinor mass generation mechanism, with the encoded symmetries maintained
by the VSR. The dynamical mass is embedded in the VSR framework through a
natural coupling to the kink solution of a \lambda \phi^{4} theory for a scalar
field \phi. Our results evince the possibility of novel effective scenarios,
derived from exotic couplings among dark spinor fields and scalar field
topological solutions.Comment: 6 pages, to appear in Phys.Lett.
Information-entropic analysis of Korteweg--de Vries solitons in the quark-gluon plasma
Solitary waves propagation of baryonic density perturbations, ruled by the
Korteweg--de Vries equation in a mean-field quark-gluon plasma model, are
investigated from the point of view of the theory of information. A recently
proposed continuous logarithmic measure of information, called configurational
entropy, is used to derive the soliton width, defining the pulse, for which the
informational content of the soliton spatial profile is more compressed, in the
Shannon's sense.Comment: 6 pages, 1 figur
On Equilibrium Prices in Continuous Time
We combine general equilibrium theory and theorie generale of stochastic
processes to derive structural results about equilibrium state prices
Non-existence of rest-frame spin-eigenstate spinors in their own electrodynamics
We assume a physical situation where gravity with torsion is neglected for an
electrodynamically self-interacting spinor that will be taken in its rest-frame
and spin-eigenstate: we demonstrate that under this circumstance no solution
exists for the system of field equations. Despite such a situation might look
artificial nevertheless it represents the instance that is commonly taken as
the basis for all computations of quantum electrodynamics.Comment: 5 page
Unfolding Physics from the Algebraic Classification of Spinor Fields
After reviewing the Lounesto spinor field classification, according to the
bilinear covariants associated to a spinor field, we call attention and unravel
some prominent features involving unexpected properties about spinor fields
under such classification. In particular, we pithily focus on the new aspects
--- as well as current concrete possibilities. They mainly arise when we deal
with some non-standard spinor fields concerning, in particular, their
applications in physics.Comment: 6 pages, accepted for publication in PL
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