A gauge invariant order parameter for monopole condensation in QCD vacuum

In this paper we improve the existing order parameter for monopole condensation in gauge theory vacuum, making it gauge-invariant from scratch and free of the spurious infrared problems which plagued the old one. Computing the new parameter on the lattice will unambiguously detect weather dual superconductivity is the mechanism for color confinement.As a byproduct we relate confinement to the existence of a finite correlation length in the gauge-invariant correlator of chromo-electric field strengths.

On the settling of small grains in dusty discs: analysis and formulae

ABSTRACT Instruments achieve sharper and finer observations of micrometre-in-size dust grains in the top layers of young stellar discs. To provide accurate models, we revisit the theory of dust settling for small grains, when gas stratification, dust inertia, and finite correlation times for the turbulence should be handled simultaneously. We start from a balance of forces and derive distributions at steady state. Asymptotic expansions require caution since limits do not commute. In particular, non-physical bumpy distributions appear when turbulence is purely diffusive. This excludes very short correlation times for real discs, as predicted by numerical simulations.

Effect of finite correlation time on the wave-particle interactions of nonlinear electrostatic structures with electrons in the Earth's radiation belts.

<p><em>In situ</em> measurements of electron scale fluctuations by the Van Allen Probes and MMS have demonstrated the ubiquitous occurrence of phase-space holes and various kinetic nonlinear structures in the Earth's magnetosphere. However it remains an open question whether phase-space holes have to be incorporated into global magnetospheric models describing the energisation and acceleration of electrons. In this communication we will review current wave-particle models of electron phase-space holes interacting with energetic electrons (e.g. >1 keV in the Earth's radiation belts)  and present new theoretical results showing that finite correlation times of phase-space holes results in enhanced pitch-angle scattering. The pitch-angle scattering by phase-space holes is shown to be on par with that produced by chorus waves, and in some instances outgrows the chorus contribution. </p><p> </p>

Non-Markovian dynamics of a three-level atom in a stochastic field with finite correlation time due to initial correlations

Dynamics of a three-level atom interacting with a stochastically fluctuating environment characterized by finite correlation time is investigated in the cases of a product initial state and a correlated initial state. The correlated initial state is obtained by the state reduction caused by the von Neumann measurement on the quantum system evolved from the product initial state and surrounded by the initially stationary stochastic environment. It is shown that in case of a pure dephasing process under the influence of a Kubo-Anderson type stochastic environment, the projective measurement causes the emergence of correlations between previously independent stochastic processes, their non-stationarity, and also causes the transition from a Markovian-type evolution to a non-Markovian one.