相关论文: Astrophysics in 2006

The universe is found to have undergone several phases in which the gravitational constant had different behaviors. During some epochs the energy density of the universe remained constant and the universe remained static. In the radiation…

In this brief review I summarize our basic knowledge about different types of isolated neutron stars. I discuss radio pulsars, central compact objects in supernova remnants, magnetars, near-by cooling neutron stars (aka the Magnificent…

A review on recent astronomical observations indicating to unexpectedly abundant population of the contemporary and $ z \sim 10 $ universe by massive black holes in all mass ranges are is presented. It is argued that these black holes are…

Since more than a century we investigate cosmic particles coming from the Universe with the aim of understanding their nature, their origin and how they are accelerated. So far, cosmic rays have provided many impressive results, giving…

Nerd abstract: Observational constraints on spacetime are reviewed, focusing on how the underlying physics (dark matter, dark energy, gravity) can be tested rather than assumed. Popular abstract: Space is not a boring static stage on which…

Neutron stars contain matter in one of the densest forms found in the Universe. This feature, together with the unprecedented progress in observational astrophysics, makes such stars superb astrophysical laboratories for a broad range of…

Astrophysics and cosmology can be used to test the standard model of particle physics under conditions and over distance and time scales not accessible to laboratory experiments. Most of the astrophysical observations are in good agreement…

Contrary to young neutron stars, young strange stars are not subject to the r-mode instability which slows rapidly rotating, hot neutron stars to rotation periods near 10 ms via gravitational wave emission. Young millisecond pulsars are…

High-energy photons are a powerful probe for astrophysics and for fundamental physics in extreme conditions. During the recent years, our knowledge of the most violent phenomena in the Universe has impressively progressed thanks to the…

Cosmology and particle physics are deeply interrelated. Among the common problems are dark energy, dark matter and baryon asymmetry of the Universe. We discuss these problems in general terms, and concentrate on several particular…

During the last century, with the development of modern physics in such diverse fields as thermodynamics, statistical physics, and nuclear and particle physics, the basic principles of the evolution of stars have been successfully well…

In the present paper we discuss a selection of facts and questions related to observations and evolutionary calculations of massive single stars and massive stars in interacting binaries. We focus on the surface chemical abundances, the…

It is believed that pulsars are neutron stars or strange stars with crusts. However we suggest here that pulsars may be bare strange stars (i.e., strange stars without crust). Due to rapid rotation and strong emission, young strange stars…

Ever since the discovery of neutron stars it has been realized that they serve as probes of a physical regime that cannot be accessed in laboratories: strongly degenerate matter at several times nuclear saturation density. Existing nuclear…

With the discovery of galaxies that existed when the universe was very young (approximately 5 percent of its current age), of planets not in our own solar system, and with the tantalizing evidence that the conditions for life may have…

Observational manifestations of far evolved stars at the asymptotic giants branch and their nearest descendants are briefly considered. Main results of their chemical composition determinations based on long term high resolution…

A star burns its nuclear fuel and balances gravitation by the pressure of the heated gas, during its active lifetime. After the exhaustion of the nuclear fuel, a low mass star finds peace as a {\em white dwarf}, where the pressure support…

Stars form in the Galaxy with a wide range in mass. If the mass is below 7% of the Sun's, then the object does not become hot enough for stable hydrogen burning. These substellar objects are called brown dwarfs. Maps of the sky at infrared…

With more than 260 extrasolar planetary systems discovered to-date, the search for habitable planets has found new grounds. Unlike our solar system, the stars of many of these planets are hosts to eccentric or close-in giant bodies. Several…

We start with a new version of Newtonian cosmology by incorporating the fact that the galaxies are losing mass due to emission of radiation. This yields accelerated recession for the galaxies. We point out that in the presence of…