75 research outputs found
Higher derivative Chern-Simons extension in the noncommutative QED
The noncommutative (NC) massive quantum electrodynamics in dimensions
is considered. We show explicitly that the one-loop effective action arising
from the integrating out the fermionic fields leads to the ordinary NC
Chern-Simons and NC Maxwell action at the long wavelength limit (large fermion
mass). In the next to leading order, the higher-derivative contributions to NC
Chern-Simons are obtained. Moreover, the gauge invariance of the outcome action
is carefully discussed. We then consider the higher-derivative modification
into the pure NC Chern-Simons Lagrangian density and evaluate the one-loop
correction to the pole of the photon propagator.Comment: 20 pages, published versio
Perturbative quantization of two-dimensional space-time noncommutative QED
Using the method of perturbative quantization in the first order
approximation, we quantize a non-local QED-like theory including fermions and
bosons whose interactions are described by terms containing higher order
space-time derivatives. As an example, the two-dimensional space-time
noncommutative QED (NC-QED) is quantized perturbatively up to O(e^2,\theta^3),
where e is the NC-QED coupling constant and \theta is the noncommutativity
parameter. The resulting modified Lagrangian density is shown to include terms
consisting of first order time-derivative and higher order space-derivatives of
the modified field variables that satisfy the ordinary equal-time commutation
relations up to O(e^2,\theta^3. Using these commutation relations, the
canonical current algebra of the modified theory is also derived.Comment: 22 pages, no figure
Impossibility of obtaining a CP-violating Euler-Heisenberg effective theory from a viable modification of QED
In this paper, we examine the CP-violating term of the Euler-Heisenberg
action. We focus in the aspects related with the generation of such a term from
a QED-like model in terms of the effective action approach. In particular, we
show that the generation of the CP-violating term is closely related with both
of vector and axial fermionic bilinears. Although, these anomalous models are
not a "viable" extension of QED, we argue that the CP-violating term in the
photon sector is obtained only from this class of models, and not from any
fundamental field theory.Comment: 6 page
Induced Maxwell-Chern-Simons Effective Action in Very Special Relativity
In this paper, we study the one-loop induced photon's effective action in the
very special relativity electrodynamics in spacetime (VSR-QED).
Due to the presence of new nonlocal couplings resulting from the VSR gauge
symmetry, we have additional graphs contributing to the and
amplitudes. From these contributions, we discuss the VSR
generalization of the Abelian Maxwell-Chern-Simons Lagrangian, consisting in
the dynamical part and the Chern-Simons-like self-couplings, respectively. We
use the VSR-Chern-Simons electrodynamics to discuss some non-Ohmic behavior on
topological materials, in particular VSR effects on Hall's conductivity. In the
dynamical part of the effective action, we observe the presence of a UV/IR
mixing, due to the entanglement of the VSR nonlocal effects to the quantum
higher-derivative terms. Furthermore, in the self-coupling aspect, we verify
the validity of the Furry's theorem in the VSR-QED explicitly.Comment: 19 pages, 3 figure
- …