Séminaires sur les aspects théoriques et expérimentaux de la gravitation
 2010 | ||||
| 16 décembre 2010 | Leor Barack University of Southampton | Gravitational self-force in extreme-mass-ratio binary inspirals The radiative inspiral of compact objects into massive black holes in galactic nuclei is a key source for LISA -- the proposed space-based gravitational-wave observatory. The inspirals are extremely effective probes of the strong-field geometry of the central black hole, with their gravitational-wave signals encoding a wealth of detailed information about this geometry. Decoding this information will require accurate (general-relativistic) theoretical templates of the gravitational waveforms, which, in turn, requires an accurate model of the orbital evolution. The inspiral dynamics can be described in a perturbative fashion in terms of an effective gravitational self-force. Knowledge of the local self-force acting on the inspiralling body is an important prerequisite in the program to model astrophysical inspirals. I will begin this talk by reviewing the general theory of the gravitational self-force in curved spacetime, and proceed to describe how this theory is being implemented today in actual calculations of the self force for inspiral orbits. I will discuss recent calculations of the conservative post-geodesic effects of the self force in Schwarzschild geometry, and highlight the way in which these calculations allow us to make a fruitful contact with post-Newtonian and Effective One Body theories. Transparents de l'exposé PDF | ||
| 18 novembre 2010 | Hermann Nicolai AEI, Golm Horaire exceptionel 14h45 | Modular realizations of hyperbolic Weyl groups, and cosmological quantum billiards Article arXiv:1010.2212 | ||
| 4 novembre 2010 | Luciano Rezzolla AEI, Golm | Using numerical relativity to explore fundamental physics and astrophysics Recent years have seen a major progress in numerical relativity and the solution of the simplest and yet among the most challenging problems in classical general relativity: that of the evolution of two objects interacting only gravitationally. I will review the results obtained so far when modelling binaries of black holes or of neutron stars and also discuss the impact these studies have in detection of gravitational-waves, in astrophysics, and in our understanding of general relativity. Transparents de l'exposé PDF | ||
| 7 octobre 2010 | Bala R. Iyer Raman Research Institute | The Detection of Gravitational waves and the Two body problem in
general relativity The search for gravitational waves and the attendant progress on the two body problem in general relativity are broadly reviewed. Transparents de l'exposé PDF | ||
| 21 septembre 2010 | George Alekseev Steklov Mathematical Institute, Moscow | Monodromy transform approach to solving integrable reductions of Einstein's field equations in General Relativity and String gravity Transparents de l'exposé PDF PPT | ||
| 10 Juin 2010 | Philippe Roche LPTA | A review of Loop Quantum Gravity and Spin-Foams In this talk I will give a review of Loop Quantum Gravity and Spin Foams and explain the results which have been obtained so far in this approach to quantum gravity. Transparents de l'exposé PDF Aticle de revue / Review Article: Critical Overview of Loops and Foams | ||
| 10 Juin 2010 | Luc Blanchet GRECO IAP | Post-Newtonian methods and applications To be observed and analyzed by the gravitational wave detectors LIGO/VIRGO on ground and LISA in space, inspiralling compact binaries (binary star systems composed of neutron stars and/or black holes) require high-accuracy predictions from general relativity. In this talk we shall review the state of the art on post-Newtonian methods as applied to the motion and gravitational radiation of these systems. We shall then compare the post-Newtonian predictions with numerical calculations of compact binaries in the small mass ratio limit using black-hole perturbation theory. Finally we shall present some recent calculations of the gravitational-wave recoil of the black hole formed by coalescence of compact binaries. Transparents de l'exposé PDF | ||
| 20 mai 2010 | Jean-Philippe Uzan IAP | Constantes fondamentales, gravitation et cosmologie Les tests de la constance des constantes fondamentales sont des tests du principe d'équivalence. Ce séminaire détaillera ce lien entre les constantes et la relativité générale puis résumera les principales contraintes expérimentales et observationnelles existantes en soulignant leur importance dans le cadre cosmologique. Transparents de l'exposé PDF | ||
| 22 Avril 2010 | Nathalie Deruelle APC | A short review of modified $f(R)$ gravity theories Einstein's general Relativity can be derived from the Hilbert Lagrangian R where R is the scalar curvature of spacetime. Very early on modified theories of gravity based of more general Lagrangian $f(R)$ were proposed, proposed, by eg H. Weyl. They were recently revived with the aim of 'explaining' dark energy. I shall review some of the interesting aspects and shortcomings of such theories. Transparents de l'exposé PDF | ||
| 25 Février 2010 | Dirk Kreimer IHES | Gravity from the view point of local quantum fields Transparents de l'exposé PDF | ||
| 21 Janvier 2010 | Philippe Brax IPhT CEA-Saclay | Chameleons in the laboratory and cosmology Transparents de l'exposé PDF | ||