296 citations · 6.5k across the 170 of their papers we have counts for
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Measuring the Chaplygin gas equation of state from angular and luminosity distances
J. S. Alcaniz, J. A. S. Lima
An exotic dark component, named generalized Chaplygin gas (Cg) and parameterized by an equation of state where and are arbitrary constants, is one of the…
Negative heat capacity and non-extensive kinetic theory
R. Silva, J. S. Alcaniz
The negative nature of the heat capacity of thermodynamically isolated self-gravitating systems is rediscussed in the framework of a non-extensive kinetic theory. It is found…
Cosmological constraints on Chaplygin gas dark energy from galaxy clusters X-ray and supernova data
J. V. Cunha, J. S. Alcaniz, J. A. S. Lima
The recent observational evidences for the present accelerated stage of the Universe have stimulated renewed interest for alternative cosmologies. In general, such models contain a…
Gravitational lensing constraints on dark energy from modified Friedmann equations
Abha Dev, J. S. Alcaniz, Deepak Jain
The existence of a dark energy component has usually been invoked as the most plausible way to explain the recent observational results. However, it is also well known that effects…
The angular size - redshift relation in power-law cosmologies
Deepak Jain, Abha Dev, J. S. Alcaniz
A linear evolution of the cosmological scale factor is a feature in several models designed to solve the cosmological constant problem via a coupling between scalar or tensor class…
Cosmological implications of APM 08279+5255, an old quasar at z = 3.91
J. S. Alcaniz, J. A. S. Lima, J. V. Cunha
The existence of old high-redshift objects provides an important tool for constraining the expanding age of the Universe and the formation epoch of the first objects. In a recent p…