76 research outputs found
A note on nonlinear electrodynamics
We explore the physical consequences of a new nonlinear electrodynamics, for
which the electric field of a point-like charge is finite at the origin, as in
the well-known Born-Infeld electrodynamics. However, contrary to the latter, in
this new electrodynamics the phenomenon of birefringence and dichroism take
place in the presence of external magnetic fields. Subsequently we study the
interaction energy, within the framework of the gauge-invariant but
path-dependent variables formalism. Interestingly enough, the static potential
profile contains a linear potential leading to the confinement of static
charges.Comment: 5 pages. arXiv admin note: substantial text overlap with
arXiv:1607.0299
D topological superconductors: screening and confinement in presence of external fields
Adopting the gauge-invariant and path-dependent variables formalism, we
compute the interaction energy for a topological field theory describing
D topological superconductors in presence of external fields. As a
result, in the case of a constant electric field- strength expectation value,
we show that the interaction energy describes a purely screening phase, encoded
in a Yukawa potential. On the other hand, in the case of a constant magnetic
field-strength and for a very small Josephson coupling constant, the
particle-antiparticle binding potential displays a linear term leading to the
confinement of static charge probes along with a screening contribution.Comment: 6 page
Remarks on the static potential in theories with Lorentz violation terms
We study the impact of Lorentz violating terms on a physical observable for
both electrodynamics of chiral matter and an Abelian Higgs-like model in
dimensions. Our calculation is done within the framework of the
gauge-invariant, but path-dependent, variables formalism. Interestingly enough,
for electrodynamics of chiral matter we obtain a logarithmic correction to the
usual static Coulomb potential. Whereas for a Abelian Higgs model with a
Lorentz-breaking term, our result displays new corrections to the Yukawa
potential.Comment: 7 page
Remarks on a model with topological mass from gauging spin
Aspects of screening and confinement are reassessed for a model
with topological mass with the gauging of spin. Our discussion is carried out
using the gauge-invariant, but path-dependent, variables formalism. We
explicitly show that the static potential profile is the sum of a Yukawa and a
linear potential, leading to the confinement of static external charges.
Interestingly enough, similar results are obtained in a theory of antisymmetric
tensor fields that results from the condensation of topological defects as a
consequence of the Julia-Toulouse mechanism.Comment: 5 page
Topological Gravity on Shift Superspace Formulation
In this contribution, we re-assess the subject of topological gravity by
following the Shift Supersymmetry formalism. The gauge-fixing of the theory
goes under the Batallin-Vilkovisky (BV) prescription based on a diagram that
contains both ghost and anti-ghost superfields, associated to the
super-vielbein and the super-Lorentz connection. We extend the formulation of
the topological gravity action to an arbitrary number of dimensions of the
shift superspace by adopting a formulation based on the gauge-fixing for
BF-type models
Photon Redshift in a Magnetic field
Previous results from the authors concerning the arising a tiny photon
anomalous paramagnetic moment are also interpreted as a red-shift in analogy to
the gravitational known effect. It is due to the photon interaction with the
magnetized virtual electron-positron background which withdraw transverse
momentum from photons and is polarization-dependent. If the photon frequency
red-shift implies a change in time, a clock would go faster for increasing
magnetic field intensity
Coulomb's law modification driven by a logarithmic electrodynamics
We examine physical aspects for the electric version of a recently proposed
logarithmic electrodynamics, for which the electric field of a point-like
charge is finite at the origin. It is shown that this electrodynamics displays
the vacuum birefringence phenomenon in the presence of external magnetic field.
Afterwards we compute the lowest-order modification to the interaction energy
by means of the gauge-invariant but path-dependent variables formalism. These
are shown to result in a long-range (-type) correction, in addition to a
linear and another logarithmic correction, to the Coulomb potential.Comment: 4 pages. arXiv admin note: text overlap with arXiv:1709.0386
Photon Mass and Very Long Baseline Interferometry
A relation between the photon mass, its frequency, , and the deflection
parameter, , determined by experimentalists (which characterizes the
contribution of space curvature to gravitational deflection) is found. This
amazing result allows us to conclude that the knowledge of the parameters
and is all we need to set up gravitational bounds on the photon mass.
By considering as inputs the most recent measurements of the solar
gravitational deflection of radio waves obtained via the Very Long Baseline
Interferometry, upper bounds on the photon mass are estimated.Comment: Accepted for publication in International Journal of Modern Physics
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