2,849 research outputs found
Pauli-Villars Regularization Elucidated in Bopp-Podolsky's Generalized Electrodynamics
We discuss an inherent Pauli-Villars regularization in Bopp-Podolsky's
generalized electrodynamics. Introducing gauge-fixing terms for Bopp-Podolsky's
generalized electrodynamic action, we realize a unique feature for the
corresponding photon propagator with a built-in Pauli-Villars regularization
independent of the gauge choice made in Maxwell's usual electromagnetism.
According to our realization, the length dimensional parameter associated
with Bopp-Podolsky's higher order derivatives corresponds to the inverse of the
Pauli-Villars regularization mass scale , i.e. .
Solving explicitly the classical static Bopp-Podolsky's equations of motion for
a specific charge distribution, we explore the physical meaning of the
parameter in terms of the size of the charge distribution. As an offspring
of the generalized photon propagator analysis, we also discuss our findings
regarding on the issue of the two-term vs. three-term photon propagator in
light-front dynamics
In-medium Yang-Mills equations: a derivation and canonical quantization
The equations for Yang-Mills field in a medium are derived in a linear
approximation with respect to the gauge coupling parameter and the external
field. The obtained equations closely resemble the macroscopic Maxwell
equations. A canonical quantization is performed for a family of Fermi-like
gauges in the case of constant and diagonal (in the group indices) tensors of
electric permittivity and magnetic permeability. The physical subspace is
defined and the gauge field propagator is evaluated for a particular choice of
the gauge. The propagator is applied for evaluation of the cross-section of
ellastic quark scattering in the Born approximation. Possible applications to
Cherenkov-type gluon radiation are commented briefly.Comment: 27 pages, references added, version extended with emphasis on
non-Abelian gauge group impact on medium characteristics. To appear in J.
Phys.
Lorenz-Mie theory for 2D scattering and resonance calculations
This PhD tutorial is concerned with a description of the two-dimensional
generalized Lorenz-Mie theory (2D-GLMT), a well-established numerical method
used to compute the interaction of light with arrays of cylindrical scatterers.
This theory is based on the method of separation of variables and the
application of an addition theorem for cylindrical functions. The purpose of
this tutorial is to assemble the practical tools necessary to implement the
2D-GLMT method for the computation of scattering by passive scatterers or of
resonances in optically active media. The first part contains a derivation of
the vector and scalar Helmholtz equations for 2D geometries, starting from
Maxwell's equations. Optically active media are included in 2D-GLMT using a
recent stationary formulation of the Maxwell-Bloch equations called
steady-state ab initio laser theory (SALT), which introduces new classes of
solutions useful for resonance computations. Following these preliminaries, a
detailed description of 2D-GLMT is presented. The emphasis is placed on the
derivation of beam-shape coefficients for scattering computations, as well as
the computation of resonant modes using a combination of 2D-GLMT and SALT. The
final section contains several numerical examples illustrating the full
potential of 2D-GLMT for scattering and resonance computations. These examples,
drawn from the literature, include the design of integrated polarization
filters and the computation of optical modes of photonic crystal cavities and
random lasers.Comment: This is an author-created, un-copyedited version of an article
published in Journal of Optics. IOP Publishing Ltd is not responsible for any
errors or omissions in this version of the manuscript or any version derived
from i
Quantum Black Hole in the Generalized Uncertainty Principle Framework
In this paper we study the effects of the Generalized Uncertainty Principle
(GUP) on canonical quantum gravity of black holes. Through the use of modified
partition function that involves the effects of the GUP, we obtain the
thermodynamical properties of the Schwarzschild black hole. We also calculate
the Hawking temperature and entropy for the modification of the Schwarzschild
black hole in the presence of the GUP.Comment: 11 pages, no figures, to appear in Physical Review
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