193 citations · 369 across the 8 of their papers we have counts for
10 papers · 1 filter
Kinematic Constraints to the Transition Redshift from SNe Ia Union Data
J. V. Cunha
The kinematic approach to cosmological tests provides a direct evidence to the present accelerating stage of the universe which does not depend on the validity of general relativit…
Can Old Galaxies at High Redshifts and Baryon Acoustic Oscillations Constrain H_0?
J. A. S. Lima, J. F. Jesus, J. V. Cunha
A new age-redshift test is proposed in order to constrain with basis on the existence of old high redshift galaxies (OHRG). As should be expected, the estimates of base…
Constraining the dark energy and smoothness-parameter with supernovae
R. C. Santos, J. V. Cunha, J. A. S. Lima
The presence of inhomogeneities modifies the cosmic distances through the gravitational lensing effect, and, indirectly, must affect the main cosmological tests. Assuming that the…
Constraining from Sunyaev-Zel'dovich effect, Galaxy Clusters X-ray data, and Baryon Oscillations
J. V. Cunha, L. Marassi, J. A. S. Lima
Estimates of from Sunyaev-Zel'dovich effect (SZE) and X-ray surface brightness of galaxy clusters depends on the underlying cosmology. In the current CDM flat cosmology, a…
Simplified Quartessence Cosmology
J. A. S. Lima, J. V. Cunha, J. S. Alcaniz
We propose a new class of accelerating world models unifying the cosmological dark sector (dark matter and dark energy). All the models are described by a simplified version of the…
New Constraints on the Variable Equation of State Parameter from X-Ray Gas Mass Fractions and SNe Ia
J. V. Cunha, L. Marassi, R. C. Santos
Recent measurements are suggesting that we live in a flat Universe and that its present accelerating stage is driven by a dark energy component whose equation of state may evolve i…