In the second self-creation theory of gravitation and in the general theory of relativity, Bianchi type VI0 cosmological model in the presence of viscous fluid is studied. An exact solution of the field equations is given by considering the cosmological model yields a constant decelerations parameter q=constant and the coefficients of the metric are taken as A(t)=[c1t+c<su...

The history of life on Earth and in other potential life-bearing planetary platforms is deeply linked to the history of the universe. Since life as we know it relies on chemical elements forged in dying heavy stars, the universe needs to be old enough for stars to form and evolve. Current cosmological theory indicates that the universe is 13.7±0.13 billion years old and that the first stars for...

the main purpose of this research is the presentation of some prerequisites of educational theorizing with regard to ontologic components of complexity paradigm. for this purpose, by using the philosophical methods, after making mention of how ontologic components of simplicity paradigm (naive realism, linear causation, determinism) influence contemporary educational theories, ontologic compone...

in order to express his visionary experiences, baha-e-valad has innovated his own symbols and imagery. such illustrations of imagination may be interpreted as the product of his intuitive experiences of visits to the realm of ideas referred to as a vision of one's self in psychological, mystic terms. the present study, in an attempt to study and analyze the nature of the symbols in baha-e-valad...

The lower limit on the age of the universe derived from globular cluster dating techniques, which previously strongly motivated a non-zero cosmological constant, has now been dramatically reduced, allowing consistency for a flat matter dominated universe with a Hubble Constant, H0 ≤ 66kms−1Mpc−1. The case for an open universe versus a flat universe with non-zero cosmological constant is reanaly...

module over a ring is a general mathematical concept for many examples of mathematicalobjects that can be added to each other and multiplied by scalar numbers.in this paper, we consider a module over a ring as a universe and by using the notion of reference points, we provide local approximations for  subsets of the universe.

We calculate the production of massive Kaluza-Klein(KK) modes via nucleon-nucleon gravi-bremsstrahlung in the early universe. Overproduction of these states would result in early matter domination and therefore a low age for the universe so it is possible to place constraints on the number and size of large extra dimensions. The constraints are stronger than those from Sn1987a.

On basis of modification of Einstein’s gravitational equations by adding the term f(R) ∝ βR , a geometric model of quintessence is proposed. The evolution equation for the scale factor a of the Universe is analyzed for the two parameters n = 2 and n = 4/3, which were preferred by previous studies of the early Universe. Another choice of parameters n and β is proposed from the following reasons:...

We show that models of generalized modified gravity, with inverse powers of the curvature, can explain the current accelerated expansion of the Universe without resorting to dark energy and without conflicting with solar system experiments. We have solved the Friedmann equations for the full dynamical range of the evolution of the Universe and performed a detailed analysis of supernovae data in...