A higher dimensional cosmological model for the search of dark energy source

With due consideration of reasonable cosmological assumptions within the limit of the present cosmological scenario, we have analyzed a spherically symmetric metric in 5D setting within the framework of Lyra manifold. The model universe is predicted to be a DE model, dominated by vacuum energy. The model represents an oscillating model, each cycle evolving with a big bang and ending at a big crunch, undergoing a series of bounces. The universe is isotropic and undergoes super-exponential expansion. The value of Hubble’s parameter is measured to be [Formula: see text] which is very close to [Formula: see text], the value estimated by the latest Planck 2018 result. A detailed discussion on the cosmological parameters obtained is also presented with graphs.

Can accelerated expansion of the universe be due to spacetime vorticity?

We present here a general relativistic mechanism for accelerated cosmic expansion and the Hubble’s parameter. It is shown that spacetime vorticity coupled to the magnetic field density in galaxies causes the galaxies to recede from one another at a rate equal to the Hubble’s constant. We therefore predict an oscillatory universe, with zero curvature, without assuming violation of Newtonian gravity at large distances or invoking dark energy/dark matter hypotheses. The value of the Hubble’s constant, along with the scale of expansion, as well as the high isotropy of CMB radiation are deduced from the model.

Bulk viscous string cosmological models in f(R) gravity

In this paper, we derive f(R) gravity field equations with the help of a spatially homogeneous and anisotropic Bianchi type-III space–time, in the presence of a bulk viscous fluid, containing one-dimensional cosmic strings. Here we obtained the solutions of the field equations, both in the presence and in the absence of cosmic strings, under some specific plausible physical conditions. In particular, cosmological models with bulk viscous strings in f(R) theory of gravity are obtained by using the special law of variation for Hubble’s parameter proposed by Berman (Nuovo Cimento, B74, 182 (1983)). Various physical and kinematical properties of the models are also discussed.

LRS Bianchi type-I cosmological model with constant deceleration parameter in f(R,T) gravity

A spatially homogeneous anisotropic LRS Bianchi type-I cosmological model is studied in [Formula: see text] gravity with a special form of Hubble's parameter, which leads to constant deceleration parameter. The parameters involved in the considered form of Hubble parameter can be tuned to match, our models with the [Formula: see text]CDM model. With the present observed value of the deceleration parameter, we have discussed physical and kinematical properties of a specific model. Moreover, we have discussed the cosmological distances for our model.

Variability of Hubble’s Parameter, Geomagnetic Activity, and Putative Changes in Space-Mass Density: Implications for Terrestrial Cell Growth

The quotient for Planck’s Length divided by the product of Hubble’s parameter and twice the width of the Compton wave length for a proton has been considered a critical increment for the time required for a proton to expand one Planck’s Length. The empirical time of 3.25 ms, found in magnetic field effectiveness for multiple physical and biochemical reactions, requires a local Hubble constant (H) of 58 km·s-1·MPar-1 with a resulting mass density of 0.14 protons per cubic meter. This mass density multiplied by the cube of the galactic orbital velocity is within error measurement of the background photon flux density measured locally by photomultiplier units over the last four years. Regression analyses for the weak positive correlation between Huchra’s annual fluctuations in H and global annual geomagnetic activity over the last 30 years indicated that every 1 nT increase was associated with 0.44 km·s-1·MPar-1 increase in H. The required average density is equivalent to that of the rest mass of the electron. The results and quantitative solutions indicate that the measurement of H is affected by geomagnetic activity and that the time for a proton to expand 1 Planck’s Length can vary over time. Unless earth-based reactions from exposures to pulsed or “quantum well” like magnetic fields that depend upon resonant precision with this value are adjusted appropriately their efficacy could vary significantly.

Experimental Evidence that Hubble’s Parameter could Be Reflected in Local Physical and Chemical Reactions: Support for Mach’s Principle of Imminence of the Universe

Mach’s principle of immanence of the universe requires the behavior of local matter to depend upon the remainder of the universe. Hubble’s constant could be employed to calculate the inference of this condition. More than a decade ago specific types of temporally patterned magnetic fields generated by serial 3 ms point durations were shown to produce conspicuous biochemical effects. When the product of this duration and the diameter of a proton was divided into Planck’s Length the estimated Hubble’ parameter was 66.7 ±1.3 km∙ s-1·MParsec-1 which is remarkably similar to the current value of 67.8 km∙ s-1. Photon emissions from chemoluminescent reactions and discrete shifts in pH within spring water during exposure to specific patterns of magnetic fields revealed optimal responses with remarkably similar z-transformations when point durations of the constructive voltages were 3 ms or 1 ms but not 2, 4, or 5 ms. Cumulative results indicate proton (3 ms) and electron (~1.5 ms) processes. These results support Mach’s contention and indicate that relatively accurate inferences of the Hubble parameter might be obtained with more precise instrumentation on the terrestrial surface.

A Finite, Open and Contingent Universe

According to today’s Cosmology the universe has a finite mass, a finite (but growing) “age”, and a finite (but growing) space-time extension. The product of Ho (Hubble’s parameter) by to (the present “age” of the universe) is at the present epoch Hotto = 0.942 ± 0.065, therefore more than 2/3 implying an open universe (k<0). A finite, open universe is contingent (it could have been otherwise) and therefore created. Quotes of Planck and Einstein on the subject are given.

STRING COSMOLOGY IN ANISOTROPIC BIANCHI-II SPACETIME

The present study deals with a spatially homogeneous and anisotropic Bianchi-II cosmological model representing massive strings. The energy–momentum tensor, as formulated by Letelier,10 has been used to construct a massive string cosmological model for which the expansion scalar is proportional to one of the components of shear tensor. The Einstein's field equations have been solved by applying a variation law for generalized Hubble's parameter that yields a constant value of deceleration parameter in Bianchi-II spacetime. A comparative study of accelerating and decelerating modes of the evolution of universe has been carried out in the presence of string scenario. The study reveals that massive strings dominate the early Universe. The strings eventually disappear from the Universe for sufficiently large times, which is in agreement with the current astronomical observations.

BIANCHI TYPE V COSMOLOGICAL MODELS WITH PERFECT FLUID AND HEAT CONDUCTION IN LYRA'S GEOMETRY

The field equations within the framework of Lyra's geometry with a time-dependent displacement vector field for a Bianchi type-V space–time filled with a perfect fluid and heat flow are presented. Two different classes of physically viable solutions are obtained by using a special law of variation for the generalized mean Hubble's parameter which correspond to singular and nonsingular models with constant deceleration parameter. These models are found to be consistent with the observations on the present day universe. Some thermodynamical relations are studied. The physical and kinematical behaviors of the models are also discussed.