We study the time variation of fundamental constants in the early Universe. Using data from primordial light nuclei abundances, cosmic microwave background, and the 2dFGRS power spectrum, we put constraints on the time variation of the fine structure constant α and the Higgs vacuum expectation value ⟨v⟩ without assuming any theoretical framework. A

We present the results of a systematic analysis of the solid state features identified in the circumstellar environments of a large sample of evolved stars with ISO/SWS and Spitzer/IRS spectroscopy. The sample includes several hundred stars with a wide variety of progenitor masses evolving from the early AGB phase to the PN stage. Our observations

We report on new results in the search for diffuse bands, signatures of still unknown origin, in the circumstellar envelopes of evolved (post-AGB) stars.

We use a combination of three large N-body simulations to investigate the dependence of dark matter halo concentrations on halo mass and redshift in the Wilkinson Microwave Anisotropy Probe year 5 (WMAP5) cosmology. The median relation between concentration and mass is adequately described by a power law for halo masses in the range 1011-1015h

Oscillations of the Sun have been used to understand its interior structure. The extension of similar studies to more distant stars has raised many difficulties despite the strong efforts of the international community over the past decades. The CoRoT (Convection Rotation and Planetary Transits) satellite, launched in December 2006, has now

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