Inflation Targeting With Special Review on Appliction in Serbia

Inflation targeting represents monetary regime primarily applied in New Zealand in 1989. Since then, this regime has extended into over 30 countries and it is recommended by International Monetary Fund within its business arrangements in last couple of years. The last country that announced this regime was Serbia. It is regularly introduced when previous one had poor performances. Its nature is determined by targeted inflation rate, high level of transparency in monetary policies conducting, absence of secondary goals, as well as responsibility for realized targeted inflation rates. Within work, theoretical presumptions are analyzed regarding implementation of this regime, and the most important aspects of its functioning in chosen countries, and its application in Serbia is a subject of particular consideration.Inflation targeting, Monetary policy, Serbia, Transparency

Gravitational waves in a stringlike fluid cosmology

The coupling of a stringlike fluid with ordinary matter and gravity may lead to a closed Universe with the dynamic of an open one. This can provide an alternative solution for the age and horizon problems. A study of density perturbations of the stringlike fluid indicates the existence of instabilities in the small wavelength limit when it is employed a hydrodynamic approach. Here, we extend this study to gravitational waves, where the hydrodynamical approach plays a less important role, and we argue that traces of the existence of this fluid must be present in the anisotropies of the cosmic background radiation.Comment: Latex, 8 page

Ruling out the Modified Chaplygin Gas Cosmologies

The Modified Chaplygin Gas (MCG) model belongs to the class of a unified models of dark energy (DE) and dark matter (DM). It is characterized by an equation of state (EoS) $p_c = B\rho - A/\rho^{\alpha}$, where the case $B=0$ corresponds to the Generalized Chaplygin Gas (GCG) model. Using a perturbative analysis and power spectrum observational data we show that the MCG model is not a sucessful candidate for the cosmic medium unless $B=0$. In this case, it reduces to the usual GCG model.Comment: Latex file, 7 pages, 6 figures in eps forma

Scalar field black holes

With a suitable decomposition of its energy-momentum tensor into pressureless matter and a vacuum type term, we investigate the spherical gravitational collapse of a minimally coupled, self-interacting scalar field, showing that it collapses to a singularity. The formed blackhole has a mass $M \sim 1/m$ (in Planck units), where $m$ is the mass of the scalar field. If the latter has the axion mass, $m \sim 10^{-5}$ eV, the former has a mass $M \sim 10^{-5} M_{\odot}$.Comment: 8 pages, no figure