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...

every kind of theorization and progress modeling, wether contiousely or uncontiousely, is based on and benefited from the epistemological, cosmological, anthropological, axiological foundations. for the iranian islamic model of progress, however, it is compulsary to recognize and refer to its own speculative understructures and use them intentionaly and exactly to produce the  best possible mod...

william lane craig, american recent philosopher has tried with appealing to cantor’s latest ideas and also theory of “big bang” in physics; present a new explanation of cosmological argument. his explanation which is called “kalam- cosmological argument” is going to describe moslem philosopher’s argument in this aspect, like kendi and ghazali. he makes efforts to refuse the doctrine of eternali...

We discuss how the modifications of standard Einstein’s equations needed to support cosmological bounce can at same time lead vanishing well known constant problem, while also studying effects spacetime fluctuations. first concentrate on case classical Friedmann–Lemaître–Robertson–Walker (FLRW) and show that in a bouncing cosmology, where modification Einstein–Hilbert action be represented by m...

Abstract. Homogeneous isotropic cosmological models with two torsion functions filled with scalar fields and usual gravitating matter are built and investigated in the framework of the Poincaré gauge theory of gravity. It is shown that by certain restrictions on indefinite parameters of gravitational Lagrangian the cosmological equations at asymptotics contain an effective cosmological constant...

Abstract. Homogeneous isotropic cosmological models with two torsion functions filled with scalar fields and usual gravitating matter are built and investigated in the framework of the Poincaré gauge theory of gravity. It is shown that by certain restrictions on indefinite parameters of gravitational Lagrangian the cosmological equations at asymptotics contain effective cosmological constant th...

Recently a covariant entropy conjecture has been proposed for dynamical horizons. We apply this conjecture to concordance cosmological models, namely, those cosmological models filled with perfect fluids, in the presence of a positive cosmological constant. As a result, we find this conjecture has a severe constraint power. Not only does this conjecture rule out those cosmological models disfav...

We study the generation of cosmological perturbations during the Hagedorn phase of string gas cosmology. Using tools of string thermodynamics we provide indications that it may be possible to obtain a nearly scale-invariant spectrum of cosmological fluctuations on scales which are of cosmological interest today. In our cosmological scenario, the early Hagedorn phase of string gas cosmology goes...