Related papers: Effective Lagrange function of intense electromagn…
The parity and time-reversal invariant effective lagrangian for a heavy fermion interacting with an abelian gauge field, i.e., NRQED, is constructed through order $1/M^4$. The implementation of Lorentz invariance in the effective theory…
We calculate the spin flip rates for an electron in a homogeneous magnetic field for low excitations ($N\le 5$). Our results apply for all field strengths including those beyond the critical field strength at which the spin contributes as…
We consider a theory of massless reduced quantum electrodynamics (RQED$_{d_\gamma,d_e}$), e.g., a quantum field theory where the U(1) gauge field lives in $d_\gamma$-spacetime dimensions while the fermionic field lives in a reduced…
An interesting class of background field configurations in QED are the O(2)xO(3) symmetric fields. Those backgrounds have some instanton-like properties and yield a one-loop effective action that is highly nontrivial but amenable to…
The running of the effective electromagnetic coupling is for many electroweak observables the dominant correction. It plays an important role for deriving constraints on the Standard Model in the context of electroweak precision…
Estimating the effective energy, $E_\text{eff}$ of a stationary probability distribution is a challenge for non-equilibrium steady states. Its solution could offer a novel framework for describing and analyzing non-equilibrium systems. In…
Using techniques of effective field theory, we consider the thermodynamical properties of a dilute two-dimensional plasma interacting via a $1/r$ potential. The first one-loop correction to the partition function is already logarithmically…
We introduce infrared finite, analytic, crossing symmetric, Regge behaved, and Lorentz invariant amplitudes $\mathcal{M}_{\mathcal {E}}$, labeled by the experimental energy resolution $\mathcal{E}$ for detecting soft photons and gravitons.…
We propose a model of a relativistic string formed by a scalar complex field, acting as electromagnetic field source. An axiosymmetric solutions of the stationary equations for the scalar and electromagnetic fields are found numerically.…
Any effective field theory relies on power counting rules that allow one to perform a systematic expansion of calculated quantities in terms of some soft scales. However, a naive power counting can be violated due to the presence of various…
1-loop quantum corrections are shown to induce large effects on the refraction index $n$ inside a graphene strip in the presence of an external magnetic field $B$ orthogonal to it. To this purpose, we use the tools of Quantum Field Theory…
The complete calculation of the 2-loop electroweak corrections to the renormalization of the electric charge in the Standard Model allows to discuss in detail the value of the MSbar effective coupling $\hat e(m_Z)$. We discuss the…
In a large class of models for Weakly Interacting Massive Particles (WIMPs), the WIMP mass $M$ lies far above the weak scale $m_W$. This work identifies universal Sudakov-type logarithms $\sim \alpha \log^2 (2\,M/m_W)$ that spoil the naive…
The electron motion in rather strong magnetic fields (when only the lowest Landau level is populated) is considered. In this case the electron kinetic energy is frozen out and the electrons are guided by slowly varied potential. Using the…
We have studied electroweak (EW) interactions in quantum hadrodynamics (QHD) effective field theory (EFT). The Lorentz-covariant EFT contains nucleon, pion, $\Delta$, isoscalar scalar ($\sigma$) and vector ($\omega$) fields, and isovector…
Effective interactions can be obtained from a renormalization group analysis in two complementary ways. One can either explicitly integrate out higher energy modes or impose given conditions at low energies for a cut-off theory. While the…
We reintroduce an alternative expression for the Lagrangian density that governs the interaction of a charged particle with external electromagnetic fields, proposed by Livens about one century ago. This Lagrangian is written in terms of…
The phenomenon of resonant energization of a relativistic quantum particle, moving in unison with an intense ElectroMagnetic Wave, is demonstrated in a semiclassical calculation. The wave nature of the quantum particle is of essence because…
We present an effective-field-theory calculation of the effect of a dimension-six operator involving the top quark on precision electroweak data via a top-quark loop. We demonstrate the renormalizability, in the modern sense, of the…
We give a recurrence relation for two-loop integrals encountered in the effective field theory of an infinitely heavy quark, Q, interacting with gluons and Nl massless quarks, q, from which we obtain exact two-loop results, in any dimension…