2k citations · 12k across the 281 of their papers we have counts for
17 papers · 1 filter
Brane Lorentz Symmetry from Lorentz Breaking in the Bulk
O. Bertolami, C. Carvalho
We propose the mechanism of spontaneous symmetry breaking of a bulk vector field as a way to generate the selection of bulk dimensions invisible to the standard model confined to t…
Deformation quantization of noncommutative quantum mechanics and dissipation
C. Bastos, O. Bertolami, N. C. Dias +1
We review the main features of the Weyl-Wigner formulation of noncommutative quantum mechanics. In particular, we present a -product and a Moyal bracket suitable for this th…
Cosmology in Portugal: The First 20 Years
Orfeu Bertolami
We reminisce on the first steps of the cosmology community in Portugal, which can be traced back to about 20 years ago, and discuss its achievements and current specificities. We a…
Weyl-Wigner Formulation of Noncommutative Quantum Mechanics
Catarina Bastos, Orfeu Bertolami, Nuno Costa Dias +1
We address the phase space formulation of a noncommutative extension of quantum mechanics in arbitrary dimension, displaying both spatial and momentum noncommutativity. By resortin…
Current tests of alternative gravity theories: the Modified Newtonian Dynamics case
Jorge Paramos, Orfeu Bertolami
We address the possibility of taking advantage of high accuracy gravitational space experiments in the Solar System and complementary cosmological tests to distinguish between the…
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…
Gravity Control Propulsion: Towards a General Relativistic Approach
O. Bertolami, F. G. Pedro
Evaluation of gravity control concepts should be examined with respect to currently known physical theories. In this work we study the hypothetical conversion of gravitational pote…
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…
Lorentz Symmetry Derived from Lorentz Violation in the Bulk
Orfeu Bertolami, Carla Carvalho
We consider bulk fields coupled to the graviton in a Lorentz violating fashion. We expect that the overly tested Lorentz symmetry might set constraints on the induced Lorentz viola…
The adventures of Spacetime
Orfeu Bertolami
We discuss how developments in physics often imply in the need that spacetime acquires an increasingly richer and complex structure. General Relativity was the first theory to show…
Berry Phase in the Gravitational Quantum Well and the Seiberg-Witten map
C. Bastos, O. Bertolami
We explicitly compute the geometrical Berry phase for the noncommutative gravitational quantum well for different SW maps. We find that they lead to different partial contributions…
The flight of the bumblebee: solutions from a vector-induced spontaneous Lorentz symmetry breaking model
Orfeu Bertolami, Jorge Paramos
The vacuum solutions arising from a spontaneous breaking of Lorentz symmetry due to the acquisition of a vacuum expectation value by a vector field are derived. These include the p…
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…
General Theory of Relativity: Will it survive the next decade?
Orfeu Bertolami, Jorge Paramos, Slava G. Turyshev
The nature of gravity is fundamental to our understanding of our own solar system, the galaxy and the structure and evolution of the Universe. Einstein's general theory of relativi…
Gravitational Quantum Well
O. Bertolami, J. G. Rosa
We discuss the implications of a model of noncommutative Quantum Mechanics where noncommutativity is extended to the phase space. We analyze how this model affects the problem of t…
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…