In the late 1990s, observations of Type IA supernovae led to the astounding discovery that the universe is expanding at an accelerating rate. The explanation for this anomalous acceleration has been one of the great problems in physics since that discovery. In this article we propose cosmological models that can explain the cosmic acceleration without introducing a cosmological constant into th...

We study numerically the inhomogeneous pre-big-bang inflation in a spherically symmetric space-time. We find that a large initial inhomogeneity suppresses the onset of the pre-big-bang inflation. We also find that even if the pre-big-bang inflationary stage is realized, the initial inhomogeneities are not homogenized. Namely, during the pre-big-bang inflation “hairs”(irregularities) do not fall...

This paper examines the Kalam cosmological argument, as put forward by William Craig. Craig infers the existence of a personal God from the supposedly finite past of the universe. The temporal finiteness of the universe is based upon philosophical arguments for the presumed impossibility of an actual infinity of past events and is confirmed by two lines of scientific evidence. The arguments aga...

We generalize previous work on inhomogeneous pre-big bang cosmology by including the effect of non-trivial moduli and antisymmetric-tensor/axion fields. The general quasi-homogeneous asymptotic solution—as one approaches the big bang singularity from perturbative initial data—is given and its range of validity is discussed, allowing us to give a general quantitative estimate of the amount of in...

The recent search for a stochastic background of gravitational waves with LIGO interferometers has produced a new upper bound on the amplitude of this background in the 100 Hz region. We investigate the implications of the current and future LIGO results on pre-Big-Bang models of the early Universe, determining the exclusion regions in the parameter space of the minimal pre-Big Bang scenario. A...

We constrain proposed phenomenological models for a vacuum energy which decays with the expansion of the universe from considerations of standard big bang nucleosynthesis. Several models which are simple enough to be physically appealing are ruled out. Typeset using REVTEX

Introduction Since the late 1990s the evolution of center-periphery relationships in Russia became complicated by an additional factor that came into play as a result of the growth of capitalism and, more specifically, the territorial expansion of big businesses into the regions. Some of Russia’s major financial-industrial groups (FIGs) and the notorious oligarchs started to re-orient their act...