Modern Physics Letters A

Until recently I had been assuming from the data taken that the dark matter wave velocity on earth is close to 25 m/s. The density of dark matter is apparently proportional to the reciprocal of the wave velocity squared. I found velocities for 2011 using my interchange method described in my 2010 Physics Essays' article. The data therein was taken near the first of May 2009. Beginning in September 2011, the large amplitude wave velocity was found near 1000 m/s, and increased to more than 20,000 m/s in October in the Northern hemisphere. Apparently one has to take into account the location and tilt of the earth in the dark matter standing wave pattern produced by the sun. I assume that the earth lies at least partially on an antinode for part of the year rather than on a node compared to most of the other planets. The antinode location and dark matter density varies on the earth's surface because the earth's orbit location and tilt varies as a function of the time of year with the tilt determining spring, summer, and winter in the Southern and Northern hemispheres.

Neutral mesons exhibit a phenomenon called flavour mixing. As a consequence of a second order weak process the flavour eigenstates corresponding to the meson and its anti-meson are superpositions of two mass eigenstates. A meson produced in a flavour state changes into an anti-meson and back again as a function of time. Such flavour oscillations are considered sensitive probes of physics beyond the Standard Model. In this brief review I summarize the status of experimental constraints on mixing parameters in the meson system.

A toy model giving rise to long-lived super-heavy particles and a small vacuum density energy, of the order of the one measured in the present universe, is presented. It consists in a hidden sector, invariant under an SU(2) gauge symmetry, with some masses provided by a specific double Higgs mechanism. It is assumed that the Standard Model particles are also charged under the SU(2) interaction, which is weak enough to allow super-heavy particles with mean lifetime with values larger than the age of the universe. The hidden fermions and the hidden Higgs are super-heavy, which mass values close to the GUT scale. In addition, there is a spontaneously broken U(1) chiral symmetry, giving rise to a pseudoscalar Goldstone boson which we refer as a "hidden axion". The vacuum energy of the universe is identified as the potential energy of this pseudoscalar.

In this study, we employ the scalar perturbations of the charged dilaton black hole (CDBH) found by Chan, Horne and Mann (CHM), and described with an action which emerges in the low-energy limit of the string theory. A CDBH is neither asymptotically flat (AF) nor non-asymptotically flat (NAF) spacetime. Depending on the value of its dilaton parameter a, it has both Schwarzschild and linear dilaton black hole (LDBH) limits. We compute the complex frequencies of the quasinormal modes (QNMs) of the CDBH by considering small perturbations around its horizon. By using the highly damped QNM in the process prescribed by Maggiore, we obtain the quantum entropy and area spectra of these black holes (BHs). Although the QNM frequencies are tuned by a, we show that the quantum spectra do not depend on a, and they are equally spaced. On the other hand, the obtained value of undetermined dimensionless constant ϵ is the double of Bekenstein's result. The possible reason of this discrepancy is also discussed.

Integrable systems satisfied by the curvatures of Cartan curves in Minkowski space under inextensible motions are identified. It is shown that motions of Cartan curves in three-, four- and n-dimensional (n > 4) Minkowski space are related to the KdV hierarchy, a coupled KdV system and a multi-component generalization of the coupled KdV system.

We investigate the dynamic polarization potential (DPP) contribution to the bare potential obtained by using double-folding model (DFM) within the framework of the Optical Model (OM) for the different density distributions of ⁶He nucleus scattered from ²⁰⁸Pb target at 22 MeV. The final results are in agreement with the experimental data. We are proposing a new parametrization of the DPP that could be very useful in other weakly bound projectile studies.

We study the bulk viscosity taking dust matter in the generalized teleparallel gravity. We consider different dark energy (DE) models in this scenario along with a time-dependent viscous model to construct the viscous equation of state (EoS) parameter for these DE models. We discuss the graphical representation of this parameter to investigate the viscosity effects on the accelerating expansion of the universe. It is mentioned here that the behavior of the universe depends upon the viscous coefficients showing the transition from decelerating to accelerating phase. It leads to the crossing of phantom divide line and becomes phantom dominated for specific ranges of these coefficients.