Séminaire / Seminar GReCO |
| « Astrophysically Realistic Initial Data for Binary Black Hole Systems » |
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Nico Yunes |
| In this talk we will discuss the construction of astrophysically realistic initial data for numerical simulations of binary non-spinning black hole systems. This data is generated by asymptotically matching perturbed Schwarzschild solutions, which are valid close to each hole (inner zones), to a post-Newtonian solution (1 PN), valid sufficiently far away from both of them (near zone). The astrophysical realism of this data is rooted in that it approaches the relevant approximate solutions to the Einstein equations in the appropriate limits. This method allows for the explicit analytic calculation of initial data (conformal metric and extrinsic curvature) as well as analytic gauge conditions (lapse and shift), which are found to be non-conformally flat and non-maximally sliced. We study this method of initial data construction by comparing the use of a Lagrangian to a Hamiltonian PN expansion in the near zone, as well as different coordinate systems in the inner zone. This method further allows us to approximately quantify the physical error and constraint violation contained in the data. We will finally point to extending this work for the case of spinning binary systems. |
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jeudi 22 septembre 2005 - 11:00 Salle des séminaires Évry Schatzman Institut d'Astrophysique de Paris |
| Pages web du séminaire / Seminar's webpage |