Related papers: Gauge Invariance in the Process $e^+e^-\to \bar \n…
The postulate of gauge invariance in nature does not lend itself directly to implementations of lattice gauge theories in modern setups of quantum synthetic matter. Unavoidable gauge-breaking errors in such devices require gauge invariance…
We study the sensitivity of the process e^+ e^- \to \nu\bar{\nu}\gamma to extra gauge bosons, particularly W' bosons. Depending on the model, evidence for extra W bosons in this process can be detected for W' masses up to several TeV.
The critical behavior of the Ginzburg-Landau model is described in a manifestly gauge-invariant manner. The gauge-invariant correlation-function exponent is computed to first order in the $4-d$ and $1/n$-expansion, and found to agree with…
I review the state of the art of the investigation on the structure formation in $f(R)$-gravity based on the Covariant and Gauge Invariant approach to perturbations. A critical analysis of the results, in particular the presence of…
A basis of Lorentz and gauge-invariant monomials in non--Abelian gauge theories with matter is described, applicable for the inverse mass expansion of effective actions. An algorithm to convert an arbitrarily given invariant expression into…
Elementary particle scatterings and decays in presence of a background magnetic field are very common in physics, specially after the observation that the core of the neutron stars can sustain a magnetic field of the order of $10^{13} {\rm…
The complete matrix elements for e^+ e^- -> 4f and e^+ e^- -> 4f + gamma are calculated in the Electroweak Standard Model for polarized massless fermions. The matrix elements for all final states are reduced to a few compact generic…
Gauge freedom in quantum electrodynamics (QED) outside of textbook regimes is reviewed. It is emphasized that QED subsystems are defined relative to a choice of gauge. Each definition uses different gauge-invariant observables. This…
In this paper we study the problems of invariant and ergodic measures under G-expectation framework. In particular, the stochastic differential equations driven by G-Brownian motion have the unique invariant and ergodic measures. Moreover,…
We realize, by Monte Carlo event generator methods, the exact O}(\alpha)$ YFS exponentiated calculation of $e^+e^- \to W^+ W^- (\to f_1\bar f'_1 + \bar f_2 f'_2)$ at and beyond LEP2 energies, where the left-handed parts of $f_i$ and $f'_i$…
We consider invariant matrix models with log-normal (asymptotic) weight. It is known that their eigenvalue distribution is intermediate between Wigner-Dyson and Poissonian, which candidates these models for describing a system intermediate…
We consider lattice implementation of the recently proposed gauge invariant definition of the monopole charge. Because of the lattice discretization the algorithm gives rise to specific lattice artifacts and an effective Ising model. The…
We perform a model-independent analysis of the spontaneously broken phase of an $SU(2)\times U(1)$ supersymmetric gauge theory, by using a non-linear parametrization of the Goldstone sector of the theory. The non-linear variables correspond…
We consider a modification of the covariance function in Gaussian processes to correctly account for known linear constraints. By modelling the target function as a transformation of an underlying function, the constraints are explicitly…
The use of gyrokinetics, wherein phase-space coordinate transformations result in a phase-space dimensionality reduction as well as the removal of fast time scales, has enabled the simulation of microturbulence in fusion devices. The…
We study the different ways of introducing light-matter interaction in first-principle tight-binding (TB) models. The standard way of describing optical properties is the velocity gauge, defined by linear coupling to the vector potential.…
Recently a new technique for the production of muon ($\mu^+$) and muonium ($\mu^+e^-$) beams of unprecedented brightness has been proposed. As one consequence and using a highly stable Mach-Zehnder type interferometer, a measurement of the…
It is shown that gravitational coupling creates inertia for the electron. The coupling term does not mix right- and left-handed spinor components. Therefore, the corresponding electroweak term is invariant under U(1) X SU(2)_L gauge…
The dynamics of gaseous stars can be described by the Euler-Poisson system. Inspired by Rein's stability result for $\gamma>{4/3}$, we prove the nonlinear instability of steady states for the adiabatic exponent $\gamma={6/5}$ in spherically…
Vector mesons and the $W$ gauge boson share some common features, such as the spin and a very short lifetime. The electromagnetic properties of the $W$ are linked to its gauge nature and thus a big effort has been devoted to measure them,…