73 citations · 361 across the 20 of their papers we have counts for
19 papers · 1 filter
Compactness bounds in General Relativity
Artur Alho, José Natário, Paolo Pani +1
A foundational theorem due to Buchdahl states that, within General Relativity (GR), the maximum compactness of a static, spherically symmetric, perfec…
Spinning cylinders in general relativity: a canonical form for the Lewis metrics of the Weyl class
L. Filipe O. Costa, José Natário, N. O. Santos
In the main article [CQG 38 (2021) 055003], a new "canonical" form for the Lewis metrics of the Weyl class has been obtained, depending only on three parameters -- Komar mass and a…
Reply to the comment on "Frame-dragging: meaning, myths, and misconceptions" by A. Deriglazov
L. Filipe O. Costa, José Natário
It has been claimed in [arXiv:2110.09522] that the expression for the Sagnac coordinate time delay given in [arXiv:2109.14641] "differs from the standard interpretation described i…
Frame-dragging: meaning, myths, and misconceptions
L. Filipe O. Costa, José Natário
Originally introduced in connection with general relativistic Coriolis forces, the term is associated today with a plethora of effects related to the off-…
Compact elastic objects in general relativity
Artur Alho, José Natário, Paolo Pani +1
We introduce a rigorous and general framework to study systematically self-gravitating elastic materials within general relativity, and apply it to investigate the existence and vi…
Addendum to "Strong cosmic censorship: The nonlinear story"
Raimon Luna, Miguel Zilhão, Vitor Cardoso +2
We clarify a number of issues that arise when extending the analysis of Strong Cosmic Censorship (SCC) to perturbations of highly charged Reissner-Nordström de Sitter (RNdS) spacet…
Riemannian manifolds dual to static spacetimes
Carolina Figueiredo, José Natário
We establish a one-to-one correspondence between static spacetimes and Riemannian manifolds that maps causal geodesics to geodesics, as suggested by L. C. Epstein. We then explore…
Mathematical relativity
José Natário
Lecture notes written for a one-semester course in mathematical relativity aimed at mathematics and physics students. Not meant as an introduction to general relativity, but rather…
Linear relativistic thermoelastic rod
Anne T. Franzen, José Natário
We derive and analyze the linearized hyperbolic equations describing a relativistic heat-conducting elastic rod. We construct a decreasing energy integral for these equations, comp…
Rigid elastic solids in relativity
José Natário
After briefly reviewing the theory of relativistic elasticity, we expand a general elastic Lagrangian to quadratic order and compute the main parameters for the linear elasticity o…
Strong cosmic censorship: The nonlinear story
Raimon Luna, Miguel Zilhão, Vitor Cardoso +2
A satisfactory formulation of the laws of physics entails that the future evolution of a physical system should be determined from appropriate initial conditions. The existence of…
Solutions of the wave equation bounded at the Big Bang
Pedro M. Girão, José Natário, Jorge Drumond Silva
By solving a singular initial value problem, we prove the existence of solutions of the wave equation which are bounded at the Big Bang in the Friedmann-Lemaitre-Robert…
Decay of solutions of the wave equation in expanding cosmological spacetimes
João L. Costa, José Natário, Pedro Oliveira
We study the decay of solutions of the wave equation in some expanding cosmological spacetimes, namely flat Friedmann-Lemaître-Robertson-Walker (FLRW) models and the cosmological r…
Cosmic no-hair in spherically symmetric black hole spacetimes
João L. Costa, José Natário, Pedro Oliveira
We analyze in detail the geometry and dynamics of the cosmological region arising in spherically symmetric black hole solutions of the Einstein-Maxwell-scalar field system with a p…
Gravitomagnetism and the significance of the curvature scalar invariants
L. Filipe O. Costa, Lode Wylleman, José Natário
The curvature invariants have been subject of interest due to the debate concerning the notions of intrinsic/extrinsic frame-dragging, the use of the electromagnetic analogy in suc…
Center of mass, spin supplementary conditions, and the momentum of spinning particles
L. Filipe Costa, José Natário
We discuss the problem of defining the center of mass in general relativity and the so-called spin supplementary condition. The different spin conditions in the literature, their p…
Spacetime dynamics of spinning particles - exact electromagnetic analogies
L. Filipe O. Costa, José Natário, Miguel Zilhão
We compare the rigorous equations describing the motion of spinning test particles in gravitational and electromagnetic fields, and show that if the Mathisson-Pirani spin condition…
Mathisson's helical motions demystified
L. Filipe O. Costa, José Natário, Miguel Zilhão
The motion of spinning test particles in general relativity is described by Mathisson-Papapetrou-Dixon equations, which are undetermined up to a spin supplementary condition, the l…
Mathisson's helical motions for a spinning particle --- are they unphysical?
L. Filipe O. Costa, Carlos A. R. Herdeiro, José Natário +1
It has been asserted in the literature that Mathisson's helical motions are unphysical, with the argument that their radius can be arbitrarily large. We revisit Mathisson's helical…