ar X iv : a st ro - p h / 05 05 55 5 v 1 2 7 M ay 2 00 5 Pulsars as Tools for Fundamental Physics & Astrophysics

ar X iv : a st ro - p h / 06 05 39 7 v 1 16 M ay 2 00 6 An Investigation of Be / X - ray Pulsars with OGLE - III Data

Received ; accepted – 2 – ABSTRACT We have studied five seasons of OGLE-III data for eight SMC Be/X-ray pulsars for which no other survey data were available. We have determined orbital periods for four of these binary systems, one of which also shows nonradial pulsations. Optical identification of SMC X-2 is reconsidered, but no periods were found for either of the two possible candidates.

ar X iv : a st ro - p h / 02 05 50 4 v 1 2 9 M ay 2 00 2 Cosmology with Varying Constants

The idea of possible time or space variations of the ‘fundamental’ constants of nature, although not new, is only now beginning to be actively considered by large numbers of researchers in the particle physics, cosmology and astrophysics communities. This revival is mostly due to the claims of possible detection of such variations, in various different contexts and by several groups. Here, I pr...

ar X iv : a st ro - p h / 06 05 06 7 v 1 2 M ay 2 00 6 Sensitivity and pointing accuracy of the NEMO km 3 telescope

ar X iv : a st ro - p h / 92 05 00 5 v 1 9 M ay 1 99 2 UCSBTH – 92 – 05 April 1992 CHAOTIC DARK MATTER

A very weakly coupled scalar field with mass m and initial vacuum expectation value V will provide enough mass to close the universe provided V ≃ (3 × 10 8 GeV)(100 GeV/m) 1/4. We discuss possible models in which such a field could arise. (a) Electronic address (internet): [email protected].

ar X iv : a st ro - p h / 05 05 09 6 v 1 5 M ay 2 00 5 1 Curvature driven acceleration : an utopia or a reality ?

The present work shows that a combination of nonlinear contributions from the Ricci curvature in Einstein field equations can drive a late time acceleration of expansion of the universe. The transit from the decelerated to the accelerated phase of expansion takes place smoothly without having to resort to a study of asymptotic behaviour. This result emphasizes the need for thorough and critical...