40,727 research outputs found
Effects of quantum deformation on the spin-1/2 Aharonov-Bohm problem
In this letter we study the Aharonov-Bohm problem for a spin-1/2 particle in
the quantum deformed framework generated by the -Poincar\'{e}-Hopf
algebra. We consider the nonrelativistic limit of the -deformed Dirac
equation and use the spin-dependent term to impose an upper bound on the
magnitude of the deformation parameter . By using the self-adjoint
extension approach, we examine the scattering and bound state scenarios. After
obtaining the scattering phase shift and the -matrix, the bound states
energies are obtained by analyzing the pole structure of the latter. Using a
recently developed general regularization prescription [Phys. Rev. D.
\textbf{85}, 041701(R) (2012)], the self-adjoint extension parameter is
determined in terms of the physics of the problem. For last, we analyze the
problem of helicity conservation.Comment: 12 pages, no figures, submitted for publicatio
Remarks on the Aharonov-Casher dynamics in a CPT-odd Lorentz-violating background
The Aharonov-Casher problem in the presence of a Lorentz-violating background
nonminimally coupled to a spinor and a gauge field is examined. Using an
approach based on the self-adjoint extension method, an expression for the
bound state energies is obtained in terms of the physics of the problem by
determining the self-adjoint extension parameter.Comment: Matches published versio
On the -Dirac Oscillator revisited
This Letter is based on the -Dirac equation, derived from the
-Poincar\'{e}-Hopf algebra. It is shown that the -Dirac
equation preserves parity while breaks charge conjugation and time reversal
symmetries. Introducing the Dirac oscillator prescription,
, in the -Dirac
equation, one obtains the -Dirac oscillator. Using a decomposition in
terms of spin angular functions, one achieves the deformed radial equations,
with the associated deformed energy eigenvalues and eigenfunctions. The
deformation parameter breaks the infinite degeneracy of the Dirac oscillator.
In the case where , one recovers the energy eigenvalues and
eigenfunctions of the Dirac oscillator.Comment: 5 pages, no figures, accepted for publication in Physics Letters
The gluon propagator from large asymmetric lattices
The Landau-gauge gluon propagator is computed for the SU(3) gauge theory on
lattices up to a size of . We use the standard Wilson action
at and compare our results with previous computations using large
asymmetric and symmetric lattices. In particular, we focus on the impact of the
lattice geometry and momentum cuts to achieve compatibility between data from
symmetric and asymmetric lattices for a large range of momenta.Comment: Poster presented at Lattice2007, Regensburg, July 30 - August 4, 200
Phase transitions and statistical mechanics for BPS Black Holes in AdS/CFT
Using the general framework developed in hep-th/0607056, we study in detail
the phase space of BPS Black Holes in AdS, for the case where all three
electric charges are equal. Although these solitons are supersymmetric with
zero Hawking temperature, it turns out that these Black Holes have rich phase
structure with sharp phase transitions associated to a corresponding critical
generalized temperature. We are able to rewrite the gravity variables in terms
of dual CFT variables and compare the gravity phase diagram with the free dual
CFT phase diagram. In particular, the elusive supergravity constraint
characteristic of these Black Holes is particulary simple and in fact appears
naturally in the dual CFT in the definition of the BPS Index. Armed with this
constraint, we find perfect match between BH and free CFT charges up to
expected constant factors.Comment: 14 pages, 5 figures, corrected typos and references adde
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