Significant progress has been made during the last 10 years toward resolving the debate over the expansion rate of the Universe. The current value of the Hubble parameter, H 0, is now arguably known with an accuracy of 10%, largely due to the tremendous increase in the number of galaxies in which Cepheid variable stars have been discovered. Increasingly accurate secondary distance indicators, m...

Abstract : Najmoddin Razi was the well-known mystics in the late 6th century and beginning of 7th century (AH). He has authored so many works in the field of Islamic mysticism. In his most significant work, Mersadolebad, he pointed out the beginning and end of the universe, the start of deportment and the extremity of development as well as the destination and goals of lover and beloved. In Raz...

We discuss some of the cosmological constraints on the evolution and persistence of life in the Universe and in hypothetical universes other than our own. We highlight the role played by the age and size of the universe, and discuss the interplay between the main-sequence stellar lifetime and the biological evolution time scale. The consequences of different versions of the inflationary univers...

We show that the current accelerated expansion of the Universe can be explained without resorting to dark energy. Models of generalized modified gravity, with inverse powers of the curvature can have late time accelerating attractors without conflicting with solar system experiments. We have solved the Friedman equations for the full dynamical range of the evolution of the Universe. This allows...

It is considered the model of the universe in which the scales of length, time and mass are related by the special relativity constant c, by the Newton gravity constant G and by the quantum mechanics constant ¯ h. The model meets constraints from the current age of the universe, from the high-redshift supernovae data, and from primordial nucleosynthesis. The model predicts the fractal structure...

The Cardassian universe is a proposed modification to the Friedmann Robertson Walker equation in which the universe is flat, matter dominated, and accelerating. Here we generalize the original Cardassian proposal to include additional variants on the FRW equation; specific examples are presented. In the ordinary FRW equation, the right hand side is a linear function of the energy density, H2 ∼ ...

We discuss some of the cosmological constraints on the evolution and persistence of life in the Universe and in hypothetical universes other than our own. We highlight the role played by the age and size of the universe, and discuss the interplay between the main-sequence stellar lifetime and the biological evolution time scale. The consequences of different versions of the inflationary univers...

We show that the current accelerated expansion of the Universe can be explained without resorting to dark energy. Models of generalized modified gravity, with inverse powers of the curvature can have late time accelerating attractors without conflicting with solar system experiments. We have solved the Friedman equations for the full dynamical range of the evolution of the Universe. This allows...

The Cardassian universe is a proposed modification to the Friedmann Robertson Walker (FRW) equation in which the universe is flat, matter dominated, and accelerating. Here we generalize the original Cardassian proposal to include additional variants on the FRW equation. Specific examples are presented. In the ordinary FRW equation, the right hand side is a linear function of the energy density,...

The Cardassian universe is a proposed modification to the Friedmann Robertson Walker equation (FRW) in which the universe is flat, matter dominated, and accelerating. In this presentation, we generalize the original Cardassian proposal to include additional variants on the FRW equation; specific examples are presented. In the ordinary FRW equation, the right hand side is a linear function of th...