24,727 research outputs found
Power spectrum and anisotropy of super inflation in loop quantum cosmology
We investigate the scalar mode of perturbation of super inflation in the
version of loop quantum cosmology in which the gauge invariant holonomy
corrections are considered. Given a background solution, we calculate the power
spectrum of the perturbation in the classical and LQC conditions. Then we
compute the anisotropy originated from the perturbation. It is found that in
the presence of the gauge invariant holonomy corrections the power spectrum is
exponentially blue and the anisotropy also grows exponentially in the epoch of
super inflation.Comment: 12 pages,4 figures,Published versio
Some new applications for heat and fluid flows via fractional derivatives without singular kernel
This paper addresses the mathematical models for the heat-conduction
equations and the Navier-Stokes equations via fractional derivatives without
singular kernel.Comment: This is a preprint of a paper whose final and definite form will be
published in Thermal Science. Paper Submitted 28/ Dec /2016; Revised
20/Jan/2016; Accepted for publication 21/Jan/201
Anatomy of decays and effects of next-to-leading order contributions in the perturbative QCD factorization approach
In this paper, we will make systematic calculations for the branching ratios
and the CP-violating asymmetries of the twenty one decays
by employing the perturbative QCD (PQCD) factorization approach. Besides the
full leading-order (LO) contributions, all currently known next-to-leading
order (NLO) contributions are taken into account. We found numerically that:
(a) the NLO contributions can provide enhancement to the LO PQCD
predictions for and , or a reduction to
\calb(\bar{B}_s^0 \to \pi^{-} K^{*+}), and we confirmed that the inclusion of
the known NLO contributions can improve significantly the agreement between the
theory and those currently available experimental measurements, (b) the total
effects on the PQCD predictions for the relevant transition form
factors after the inclusion of the NLO twist-2 and twist-3 contributions is
generally small in magnitude: less than enhancement respect to the
leading order result, (c) for the "tree" dominated decay and the "color-suppressed-tree" decay ,
the big difference between the PQCD predictions for their branching ratios are
induced by different topological structure and by interference effects among
the decay amplitude and : constructive for the
first decay but destructive for the second one, and (d) for \bar{B}_s^0 \to
V(\eta, \etar) decays, the complex pattern of the PQCD predictions for their
branching ratios can be understood by rather different topological structures
and the interference effects between the decay amplitude \cala(V\eta_q) and
\cala(V\eta_s) due to the \eta-\etar mixing.Comment: 18 pages, 2 figures, 3 tables. Some modifications of the text.
Several new references are adde
- …
