Integrated Machian Model of a Light Speed Rotating Universe

Unification point of view, quantum cosmology must be given a priority and one should make a note that, Spin is a basic property of quantum physics and rotation is a very common experience. In this context, we have developed a quantum model of cosmology associated with Machian universe having Planck scale origin, total dark matter, light speed rotation and equality of gravitational self energy density and thermal energy density. We would like to appeal that, observed cosmic radius and age seem to be shortened by 146.3 times their actual magnitudes.

Closed Timelike Curves, Singularities and Causality: A Survey from Gödel to Chronological Protection

I give a historical survey of the discussions about the existence of closed timelike curves in general relativistic models of the universe, opening the physical possibility of time travel in the past, as first recognized by K. Gödel in his rotating universe model of 1949. I emphasize that journeying into the past is intimately linked to spacetime models devoid of timelike singularities. Since such singularities arise as an inevitable consequence of the equations of general relativity given physically reasonable assumptions, time travel in the past becomes possible only when one or another of these assumptions is violated. It is the case with wormhole-type solutions. S. Hawking and other authors have tried to “save” the paradoxical consequences of time travel in the past by advocating physical mechanisms of chronological protection; however, such mechanisms remain presently unknown, even when quantum fluctuations near horizons are taken into account. I close the survey by a brief and pedestrian discussion of Causal Dynamical Triangulations, an approach to quantum gravity in which causality plays a seminal role.

General Relativity Requires Absolute Space and Time

We examine two far-reaching and somewhat heretic consequences of General Relativity. (i) It requires a cosmology which includes a preferred rest frame, absolute space and time. (ii) A rotating universe and time travel are strict solutions of General Relativity.

Closed Timelike Curves and Singularities

Discovered in 1949 by Kurt Gödel, the homogeneous rotating universe model contains closed timelike curves and therefore allows for travel into the past, accompanied by all its paradoxes.

Interaction of anisotropic dark energy fluid with perfect fluid in the presence of cosmological term Λ

Considering the locally rotationally symmetric (LRS) Bianchi type-I metric with cosmological constant [Formula: see text], Einstein’s field equations are discussed based on the background of anisotropic fluid. We assumed the condition A = B[Formula: see text] for the metric potentials A and B, where m is a positive constant to obtain the viable model of the Universe. It is found that [Formula: see text] is positive and inversely proportional to time. The values of matter-energy density [Formula: see text], dark energy density [Formula: see text] and deceleration parameter q are found to be consistent with the values of WMAP observations. State finder parameters and anisotropic deviation parameter are also investigated. It is also observed that the derived model is an accelerating, shearing and non-rotating Universe. Some of the asymptotic and geometrical behaviors of the derived models are investigated with the age of the Universe.