2k citations · 12k across the 281 of their papers we have counts for
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WMAP5 constraints on the unified model of dark energy and dark matter
T. Barreiro, O. Bertolami, P. Torres
We derive constraints on the parameter space of the unified model of dark energy and dark matter, the Generalized Chaplygin Gas (GCG), from the amplitudes and positions of the firs…
Dark Energy-Dark Matter Interaction from the Abell Cluster A586
Orfeu Bertolami, Francisco Gil Pedro, Morgan Le Delliou
We find that deviation from the virial equilibrium of the Abell Cluster A586 yields evidence of the interaction between dark matter and dark energy. We argue that this interaction…
Perturbative approach for mass varying neutrinos coupled to the dark sector in the generalized Chaplygin gas scenario
Alex E. Bernardini, O. Bertolami
We suggest a perturbative approach for generic choices for the universe equation of state and introduce a novel framework for studying mass varying neutrinos (MaVaN's) coupled to t…
Solar system tests of scalar field models with an exponential potential
J. Paramos, O. Bertolami
We consider a scenario where a scalar field has dynamics ruled by an exponential potential, such as those arising from some quintessence type models, and aim at obtaining phenomeno…
Dark Energy-Dark Matter Interaction from the Abell Cluster A586 and violation of the Equivalence Principle
Morgan Le Delliou, O. Bertolami, F. Gil Pedro
We find that the Abell Cluster A586 exhibits evidence of the interaction between dark matter and dark energy and argue that this interaction suggests evidence of violation of the E…
Do f(R) theories matter?
O. Bertolami, J. Paramos
We consider a modified action functional with a non-minimum coupling between the scalar curvature and the matter Lagrangian, and study its consequences on stellar equilibrium. Part…
The Abell Cluster A586 and the Detection of the Equivalence Principle
O. Bertolami, F. Gil Pedro, M. Le Delliou
We discuss the current bounds on the Equivalence Principle, in particular from structure formation and, reexamine in this context, the recent claim on the evidence of the interacti…
Dark Energy-Dark Matter Interaction and putative violation of the Equivalence Principle from the Abell Cluster A586
O. Bertolami, F. Gil Pedro, M. Le Delliou
We show that the Abell Cluster A586 exhibits evidence of the interaction between dark matter and dark energy and argue that this interaction implies a violation of the Equivalence…
Lorentz symmetry from Lorentz violation in the bulk
Orfeu Bertolami, Carla Carvalho
We consider the mechanism of spontaneous symmetry breaking of a bulk vector field to study signatures of bulk dimensions invisible to the standard model confined to the brane. By a…
The electromagnetic coupling and the dark side of the Universe
M. C. Bento, O. Bertolami, P. Torres
We examine the properties of dark energy and dark matter through the study of the variation of the electromagnetic coupling. For concreteness, we consider the unification model of…
Dark Energy, Dark Matter and Gravity
Orfeu Bertolami
We discuss the motivation for high accuracy relativistic gravitational experiments in the Solar System and complementary cosmological tests. We focus our attention on the issue of…
Observational constraints on modified gravity models and the Poincaré dodecahedral topology
M. C. Bento, O. Bertolami, M. J. Rebouças +1
We study the constraints that spatial topology may place on the parameters of models that account for the accelerated expansion of the universe via infrared modifications to genera…
Chaplygin inspired Inflation
O. Bertolami, V. Duvvuri
We discuss chaotic inflation in the context of a phenomenological modification of gravity inspired by the Chaplygin gas equation of state. We find that all observationalconstraints…
Gamma Ray Bursts as Cosmological Probes
O. Bertolami, P. T. Silva
We discuss the prospects of using Gamma Ray Bursts (GRBs) as high-redshift distance estimators, and consider their use in the study of two dark energy models, the Generalized Chapl…
Supernovae constraints on dark energy and modified gravity models
M. C. Bento, O. Bertolami, N. M. C. Santos +1
We use the Type Ia Supernova gold sample to constrain the parameters of dark energy models namely the Cardassian, Dvali-Turner (DT) and generalized Chaplygin gas (GCG) models. In o…
The Chaplygin dark star
O. Bertolami, J. Paramos
We study the general properties of a spherically symmetric body described through the generalized Chaplygin equation of state. We conclude that such object, dubbed generalized Chap…
Gamma-ray bursts as dark energy-matter probes in the context of the generalized Chaplygin gas model
O. Bertolami, P. T. Silva
In this paper we consider the use of Gamma Ray Bursts (GRBs) as distance markers to study the unification of dark energy and dark matter in the context of the so-called Generalized…
Pioneer Anomaly and the Kuiper Belt mass distribution
O. Bertolami, P. Vieira
Pioneer 10 and 11 were the first probes sent to study the outer planets of the Solar System and Pioneer 10 was the first spacecraft to leave the Solar System. Besides their already…
Dark Energy - Dark Matter Unification: Generalized Chaplygin Gas Model
Orfeu Bertolami
We review the main features of the generalized Chaplygin gas (GCG) proposal for unification of dark energy and dark matter and discuss how it admits an unique decomposition into da…
Varying Electromagnetic Coupling and Primordial Magnetic Fields
O. Bertolami, R. Monteiro
We study the effect of variations of the electromagnetic coupling on the process of generation of primordial magnetic fields. We find that only through a significant growth of the…
Supernovae constraints on models of dark energy revisited
M. C. Bento, O. Bertolami, N. M. C. Santos +1
We use the Type Ia Supernova gold sample data of Riess {\it et al} in order to constrain three models of dark energy. We study the Cardassian model, the Dvali-Turner gravity modifi…
Astrophysical Constraints on Scalar Field Models
O. Bertolami, J. Paramos
We use stellar structure dynamics arguments to extract bounds on the relevant parameters of scalar field models: the putative scalar field mediator of a fifth force with a Yukawa p…
The Revival of the Unified Dark Energy-Dark Matter Model ?
M. C. Bento, O. Bertolami, A. A. Sen
We consider the generalized Chaplygin gas (GCG) proposal for unification of dark energy and dark matter and show that it admits an unique decomposition into dark energy and dark ma…
Challenges to the Generalized Chaplygin Gas Cosmology
O. Bertolami
The generalized Chaplygin gas (GCG) model allows for an unified description of the cosmologically recent accelerated expansion of the Universe and of the evolution of energy densit…