Allowed charge transfers between coherent conductors driven by a time-dependent scatterer

We derive constraints on the statistics of the charge transfer between two conductors in the model of arbitrary time-dependent instant scattering of non-interacting fermions at zero temperature. The constraints are formulated in terms of analytic properties of the generating function: its zeroes must lie on the negative real axis. This result generalizes existing studies for scattering by a time-independent scatterer under time-dependent bias voltage.Comment: 5 pages, no figures, corrected misprints and minor changes in version

Factorization of quantum charge transport for non-interacting fermions

We show that the statistics of the charge transfer of non-interacting fermions through a two-lead contact is generalized binomial, at any temperature and for any form of the scattering matrix: an arbitrary charge-transfer process can be decomposed into independent single-particle events. This result generalizes previous studies of adiabatic pumping at zero temperature and of transport induced by bias voltage.Comment: 13 pages, 3 figures, typos corrected, references adde

Non-dopplerian cosmological redshift parameters in a model of graviton-dusty universe

Possible effects are considered which would be caused by a hypothetical superstrong interaction of photons or massive bodies with single gravitons of the graviton background. If full cosmological redshift magnitudes are caused by the interaction, then the luminosity distance in a flat non-expanding universe as a function of redshift is very similar to the specific function which fits supernova cosmology data by Riess et al. From another side, in this case every massive body, slowly moving relatively to the background, would experience a constant acceleration, proportional to the Hubble constant, of the same order as a small additional acceleration of Pioneer 10, 11.Comment: 5 pages. It was presented: at SIGRAV'2000 Congress, Italy (this version); in Proc. of the Int. Symp. "FFP 4" (9-13 Dec 2000, Hyderabad, India), Sidharth& Altaisky, Eds., Kluwer Academic/Plenum, 2001;in Proc. of the 4th Edoardo Amaldi Conference on GW (Perth, W. Australia, 8-13 July 2001

Staggered-flux normal state in the weakly doped t-J model

A normal (non-superconducting) ground state of the t-J model may be variationally approximated by a Gutzwiller-projected wave function. Within this approximation, at small hole doping near half-filling, the normal state favors staggered-flux ordering. Such a staggered-flux state may occur in vortex cores of underdoped high-temperature cuprate superconductors. From comparing the energies of the staggered-flux state and of the superconducting state, we numerically obtain the condensation energy. Extracting the superfluid density directly from the projected superconducting wave function, we can also estimate the coherence length at zero temperature.Comment: 5 pages, 4 figure

On the polarization properties of the charmed baryon Lambda^+_c in the Lambda^+_c -> p + K^- + pi^+ + pi^0 decay

The polarization properties of the charmed Lambda^+_c baryon are investigated in weak non-leptonic four-body Lambda^+_c -> p + K^- + pi^+ + pi^0 decay. The probability of this decay and the angular distribution of the probability are calculated in the effective quark model with chiral U(3)XU(3) symmetry incorporating Heavy Quark Effective theory (HQET) and the extended Nambu-Jona-Lasinio model with a linear realization of chiral U(3)XU(3) symmetry. The theoretical value of the probability of the decay Lambda^+_c -> p + K^- + pi^+ + pi^0 relative to the probability of the decay Lambda^+_c -> p + K^- + pi^+ does not contain free parameters and fits well experimental data. The application of the obtained results to the analysis of the polarization of the Lambda^+_c produced in the processes of photo and hadroproduction is discussed.Comment: 10 pages, no figures, Late