Related papers: QED Effective Action Revisited
A dispersion integral representation of the Heisenberg-Euler QED effective lagrangian is derived, with Faddeev's quantum dilogarithm as a generalized Borel kernel. The nonperturbative imaginary part of the effective lagrangian is expressed…
Some field theoretical aspects, such as the effective action and Schwinger pair production, are critically reviewed in strong QED. The difference of the boundary conditions on the solutions of the field equation is discussed to result in…
We present the one-loop effective action of a quantum scalar field with DSR1 space-time symmetry as a sum over field modes. The effective action has real and imaginary parts and manifest charge conjugation asymmetry, which provides an…
We study the semiclassical expansion of the effective action for a Regge state-sum model and its dependence on the choice of the path-integral measure and the spectrum of the edge lengths. If the positivity of the edge lengths is imposed in…
We study two-loop quantum corrections to the low-energy effective actions in N=(2,2) and N=(4,4) SQED in the Coulomb branch. In the latter model, the low-energy effective action is described by a generalized Kahler potential which depends…
Different aspects of the Verlinde and Verlinde relation between high-energy effective scattering in QCD and a two-dimensional sigma-model are discussed. Starting from a lattice version of the truncated 4-dimensional Yang-Mills action we…
Known as a symmetry of vacuum Maxwell equations, the electric-magnetic duality can be lifted actually to a symmetry of an action. The Lagrangian of this action is written in terms of two vector potentials, one electric and one magnetic, and…
Quantum electrodynamics (QED) in a strong constant magnetic field is investigated from the viewpoint of its connection with noncommutative QED. It turns out that within the lowest Landau level (LLL) approximation the 1-loop contribution of…
In this paper we investigate vacuum nonlinear electrodynamics corrections on rapidly rotating pulsar radiation and spin-down in the perturbative QED approach (post-Maxwellian approximation). An analytical expression for the pulsar's…
Using a generalized proper-time method, we obtain expressions for the fermion density and the QED effective Lagrangian for an external magnetic field at finite chemical potential. The effective Lagrangian and the density are here written in…
We study two-loop Euler-Heisenberg effective actions in three-dimensional N=2 and N=4 supersymmetric quantum electrodynamics (SQED) without Chern-Simons term. We find exact expressions for propagators of chiral superfields interacting with…
We derive a recursion relation of the Feynman diagrams of the effective action for the third Legendre transformation in case of the bosonic field theory with cubic interaction. We apply the recursion relation to obtain the Feynman diagrams…
The demonstration that the electromagnetic fields derived from the Lienard-Wiechert potentials do not satisfy the Maxwell equations is proved to be false. Errors were made in the computation of the derivatives of retarded quantities. The…
Comparison of three different regularization methods of calculating the one-loop effective Heisenberg-Euler Lagrangian of quantum electro-dynamics (QED) is employed to derive some interesting integrals involving the asymptotic expansion of…
At energies much less than the electron mass $m$ the effects of quantum fluctuations in the vacuum due to virtual electron loops can be included by extending the Maxwell Lagrangian by additional non-renormalizable terms corresponding to the…
We evaluate the exact $QED_{2+1}$ effective action for fermions in the presence of a family of static but spatially inhomogeneous magnetic field profiles. This exact result yields an all-orders derivative expansion of the effective action,…
In the $\mathcal{N}=2$, $d=3$ superspace, we consider a higher-derivative generalization of the supersymmetric quantum electrodynamics, where the higher-derivative operator is a polynomial function of the d'Alembertian with arbitrary…
Effective equations are often useful to extract physical information from quantum theories without having to face all technical and conceptual difficulties. One can then describe aspects of the quantum system by equations of classical type,…
In this contribution we study the accuracy of various forms of electron effective mass equation in reproducing spectral and spin-related features of quantum dot systems. We compare the results of the standard 8 band k.p model to those…
We introduce classical and quantum antifields in the reparametrization-invariant effective action, and derive a deformed classical master equation.