SIGNS AND COSMOLOGY

Cosmic Walls and Filaments Formation in Modied Chaplygin Gas Cosmology

We want to study the perturbation growth of an initial seed of an ellipsoidal shape in Top-Hat collapse model of the structure formation in the Modied Chaplygin gas cosmology. Considering reasonable values of the constants and the parameters of the model under study, we can show that a very small deviation from spherical symmetry (ellipsoidal geometry) in the initial seed leads to a nal highly ...

String Cosmology versus Standard and Inflationary Cosmology

This paper presents a review of the basic, model-independent differences between the pre-big bang scenario, arising naturally in a string cosmology context, and the standard inflationary scenario. We use an unconventional approach in which the introduction of technical details is avoided as much as possible, trying to focus the reader’s attention on the main conceptual aspects of both scenarios...

Cosmology: The Noncommutative Quantum and Classical Cosmology

During the early days of quantum mechanics and quantum field theory, continuous space-time and Lorentz symmetry was considered inappropriate to describe the small scale structure of the universe. It was also argued that one should introduce a fundamental length scale, limiting the precision of position measurements. The introduction of fundamental length is suggested to cure the ultraviolet div...

Golf Signs GOLF SIGNS

Cosmology ?

It is postulated that the action of the FRW-universe is the cos-mological term of Einstein's theory (no curvature term-" R 0 Cos-mology "). The expansion equation emerging from the embedding of this most simple brane world with variable speed of light is deduced. The universal dimensionless coupling constant of gravity is addressed. Some implications on the deep problems of cosmology are discus...