The nature of the first generation of stars in the universe remains largely unknown. Observations imply the existence of massive primordial stars early in the history of the universe, and the standard theory for the growth of cosmic structure predicts that structures grow hierarchically through gravitational instability. We have developed an ab initio computer simulation of the formation of pri...

An introduction to modern theories for the origin of structure in the Universe is given. After a brief review of the growth of cosmological perturbations in an expanding Universe and a summary of some important observational results, the lectures focus on the inflationary Universe scenario and on topological defect models of structure formation. A summary of the theory and current observational...

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...

How to describe a black hole embedded in an expanding universe is an important topic. Many models about this issue are suggested by assuming that the metric is a conformal transformation of the Schwarzschild metric or of the isotropic black hole metric. In the paper, it is shown that the two metrics are not suitable for describing a black hole embedded in an expanding universe because of the si...

This paper invokes the axiomatic approach to explore the notion of growing awareness in the context of decision making under uncertainty. It introduces a new approach to modeling the expanding universe of a decision maker in the wake of becoming aware of new consequences, new acts, and new links between acts and consequences. The expanding universe, or state space, is accompanied by extension o...

X iv :g rqc /0 31 01 36 v1 3 1 O ct 2 00 3 Non commutative quantum spacetime with topological vortex states, and dark matter in the Universe Ajay Patwardhan Physics Department, St. Xavier’s college, Mahapalika Marg, Mumbai, 400001, India Abstract Non commutative geometry is creating new possibilities for physics. Quantum spacetime geometry and post inflationary models of the universe with matte...

Recently we have shown that (3+1)-dimensional expanding universe appears dynamically and uniquely from the Lorentzian version of the IIB matrix model, which is considered as a nonperturbative formulation of superstring theory. Similarly, it is possible that the Standard Model appears uniquely at the electroweak scale from the same model at late times. In order to pursue such a possibility, we d...

HROUGHOUT HUMAN HISTORY, there have been three cosmic paradigms commonly invoked to explain the nature of the universe. Each has been embodied in a modern cosmological model based on Einstein’s general theory of relativity. One is the notion of an Unchanging Universe, which underlies Einstein’s static universe model (the first cosmological model proposed after the introduction of General Relati...