Advances in Astrophysics

3

Authors: Paul Halpern, Nick Tomasello

Because of the expansion of space and the finite age of the cosmos, there exists a horizon beyond which the light emitted by objects will never be able to reach us, marking the bounds of the observable universe. One can calculate the current distance to the horizon by tracing the amount of time it would have taken a photon starting from an object currently there to have reached us. In a 2005 paper, Gott et al. derived this distance using first year CMB data from the WMAP survey. However, more recent CMB data collected by the Planck satellite and published in 2013 have since yielded different values of cosmological parameters. In this paper, we have applied these updated parameters to refine the distance to the edge of the observable universe. We have determined a revised value for the radius of the observable universe that is 0.7% smaller than the previous estimate.

14

Authors: Ya. N. Istomin

From the analysis of the flux of high energy particles, E > 3·1018eV , it is shown that the distribution of the power density of extragalactic rays over energy is of the power law, q¯(E) ∝ E −2.7 , with the same index of 2.7 that has the distribution of Galactic cosmic rays before so called knee, E < 3 · 1015eV . However, for the average power of extragalactic sources, which is of E ' 1043erg s−1 , at least two orders exceeds the power emitted by the Galaxy in cosmic rays, assuming that the density of galaxies is estimated as Ng ' 1M pc−3 . Considering that such power can be provided by relativistic jets from active galactic nuclei with the power E ' 1045 − 1046erg s−1 , we estimate the density of extragalactic sources of cosmic rays as Ng ' 10−2 − 10−3 M pc−3 . Assuming the same nature of Galactic and extragalactic rays, we conclude that the Galactic rays were produced by a relativistic jet emitted from the Galactic center during the period of its activity in the past. The remnants of a bipolar jet are now observed in the form of bubbles of relativistic gas above and below the Galactic plane. The break, observed in the spectrum of Galactic rays (knee), is explained by fast escape of energetic particles, E > 3 · 1015eV , from the Galaxy because of the dependence of the coefficient of diffusion of cosmic rays on energy, D ∝ E 0.7 . The obtained index of the density distribution of particles over energy, N(E) ∝ E −2.7−0.7/2 = E −3.05, for E > 3 · 1015eV agrees well with the observed one, N(E) ∝ E −3.1 . Estimated time of termination of the jet in the Galaxy is 4.2 · 104 years ago.

14

Authors: V.U.M.Rao, G. Suryanarayana, Y.Aditya

A new class of a spatially homogeneous and anisotropic Bianchi type V cosmological models of the universe for viscous fluid distribution within the framework of general relativity is investigated by applying suitable functional form for the Hubble parameter H which yields models of the universe that describe an early deceleration and late time acceleration. We have found that cosmological term Λ being very large at initial times relaxes to a genuine cosmological constant at late times. The physical and kinematical parameters of the models are discussed. The models are found to be compatible with the results of recent observations.

23

Authors: Gagik Ter-Kazarian

In previous paper [1], we employ the microscopic theory of black hole to study the observed unusual high luminosity of NuSTAR X-ray pulsations from M82X-2 without the need for significant breaking of Eddington limit. Exploring a spontaneous breaking of gravitation gauge symmetry at huge energies, this theory has smeared out a central singularity of black hole replacing it by the equilibrium, so-called, superdense proto-matter core (SPC), subject to certain rules. In this framework, we think of a M82X-2 as being a spinning intermediate mass black hole. However, for rigorous theoretical solutions, in present report we analytically treat the microscopic model of stationary and axisymmetric rotating black hole. A ring singularity of the Kerr black hole cannot occur, which is now replaced by equilibrium SPC. We calculate the corrections to previous model, introduced by the rotation, of the characteristic phase profile of M82X-2.

3

Authors: Dapeng Qian

Based on an improved special relativity that accommodates to the uncertainty principle, a theoretical relationship between the Hubble constant and several fundamental constants has been derived, resulting in the calculated value of H0=70.937km·s-1·Mpc-1, which compares extremely well with current measured results. The new equation and underlying theory also shed new light into the mystery of the Dirac large numbers problem. Finally, this paper mentions also an important experiment to test the improved special relativity.

7

Authors: Lukasz Andrzej Glinka, Patrick Linker

Quantum General Relativity of a higher dimensional Riemannian manifold being an embedded space in a space-time being a Lorentzian manifold is investigated through a technique of differential topology. Consequently, in the reduced model of quantum geometrodynamics, the Wheeler-DeWitt equation is replaced through a first order functional quantum evolution and a supplementary eigenequation for a scalar curvature of an embedded space. The phenomenological approach, in the framework of objective quantum gravity and global one-dimensional conjecture, is applied in order to make the standard formalism of quantum mechanics applicable to quantum gravity, beyond a Feynman path integral and a Wilson loop techniques. It leads to the wave function which refers to quantum tunnelling through a manifestly exponential form and is determined through energy density of matter fields and a cosmological constant, and physical interpretation of quantum gravity through the Tomonaga-Schwinger equation and the Dirac interaction picture of relativistic quantum mechanics. The resulting model of quantum gravity creates the opportunity of potentially new theoretical and phenomenological applications for astrophysics, cosmology, and physics.

7

Authors: Shri Ram, S. Chandel, M. K. Verma

In this paper, we obtain an anisotropic general Bianchi type cosmological model in the presence of a bulk viscous fluid. The exact solution of Einstein’s field equations is obtained by utilizing a special form of time-varying deceleration parameter that gives an early decelerating and late-time accelerating model of the universe. The physical and geometrical features of the cosmological model are discussed during the evolution of the universe. We observed that the universe accelerates in time and asymptotically tends towards a static homogeneous universe.

10

Authors: Robert L. Shuler

This paper investigates a least-time (or fastest-path) two-point algorithm for numerically propagating a light ray in a gravitational field using anisotropic coordinate velocity and distantobserver coordinates. Rather than imaging or ray tracing, the objective is to support analysis of fundamentals and to be able to find null geodesics in arbitrary metrics. First we establish that results agree with geodesic paths in regard to bending angles to very high accuracy. Then we investigate the bending rate of two coordinate bending angles, wave and displacement, and find that wave angle illustrates well-known points about spatial and time components of light bending, while the displacement angle leads to simple analytic description of Einstein’s comment about the relation between these components, and a new figure showing the compatibility of light bending and equivalence. A second analysis compares light bending near a neutron star for Schwarzschild and one alternate metric to evaluate feasibility of future experiments. Two methods of extension to non-light speed objects are discussed.

7

Authors: Robert L. Shuler

In the 1960s experiments investigating anisotropy of inertia relative to solar or galactic mass centers using the Mössbauer effect obtained negative results. Both sides of a debate over Mach’s Principle claimed the result was what should be expected. However in light of earlier comments by Einstein on the relativity of inertia to masses, Brans and Dicke felt a revised theory of gravity would better incorporate Mach’s Principle. We present a new view that the old experiment assumed, incorrectly, that Mach’s Principle affects only time dilation, which would violate the Equivalence Principle, and that the results were a predictable coordinate artifact. Using a special formalism of Distant Inertial and Spatially Homogeneous coordinates we give a plausible analysis that radial spatial distortion in a gravitational field is also related to Mach’s Principle and embodies the expected anisotropy while keeping equivalence locally intact. This leads to a view of momentum interactions via the space-time field that invites further analysis. Also, since Mach’s principle seems to be related to both time and spatial curvature, we briefly discuss whether it could be used as a postulate basis for space-time and how this might affect experiments designed to detect or exclude matter-coupled fields.

10

Authors: V.U.M.Rao, G. Suryanarayana, Y.Aditya

Spatially homogeneous Kantowski-Sachs cosmological model filled with barotropic fluid and dark energy is obtained in a scalar tensor theory of gravitation proposed by Brans and Dicke (1961). We consider both cases when the dark energy is minimally coupled to barotropic fluid as well as directly interacts with it. In these two cases the EoS parameter of dark energy is in good agreement with the observational data. Also some important features of the models, thus obtained, have been discussed.

14

Authors: Dimitrie Olenici

During the Mercury transit on 1 November 206, the inferior conjunction of Mercury on 14 July 209, and the ocultation of Mercury on 17 November 2015, a series of experiments were caried outo check for anomalous pendulum behaviour. The results confirm the apearance of anomalous variations in the sped of precesion of the plane of oscilation of the pendulum (the so-caled Alais efect), anomalous variations of the period of oscilation of the pendulum (the so caled Jeverdan-Rusu-Antonescu efect), anomalous variations of the proportion betwen the major and minor semi axes of thelipse of oscilation of the pendulum, and anomalies in the chirality of revolutionof the pendulum around its elipse of oscilation.