In a second-order r-mode theory, Sá & Tomé found that the r-mode oscillation in neutron stars (NSs) could induce stellar differential rotation, which leads to a saturation state of the oscillation spontaneously. Based on a consideration of the coupling of the rmodes and the stellar spin and thermal evolutions, we carefully investigate the influences of the r-mode-induced differential rotation o...

The r-modes of neutron stars can be driven unstable by gravitational radiation. While linear perturbation theory predicts the existence of this instability, linear theory can’t provide any information about the nonlinear development of the instability. The subject of this paper is the weakly nonlinear regime of fluid dynamics. In the weakly nonlinear regime, the nonlinear fluid equations are ap...

We investigate inertial mode oscillations of slowly and uniformly rotating, isentropic, Newtonian stars. Inertial mode oscillations are induced by the Coriolis force due to the star’s rotation, and their characteristic frequencies are comparable with the rotation frequency Ω of the star. So called r-mode oscillations form a sub-class of the inertial modes. In this paper, we use the term “r-mode...

This paper contains some reflections about using 3D topology, and more generally some 3D concepts related to 3D cadastre. Firstly, we develop some conceptual views about 3D modelling and more specifically about the definition of 3D spatial objects. Secondly, we present a new framework for representing spatial relationships. The framework has different “complexity” levels and allows mixing simpl...