Hamiltonian relaxation
نویسنده
چکیده
Due to the complexity of the required numerical codes, many of the new formulations for the evolution of gravitational fields in numerical relativity are not tested on binary evolutions. We introduce in this paper a new testing ground for numerical methods based on the simulation of binary neutron stars. This numerical set-up is used to develop a new technique, the Hamiltonian relaxation (HR), that is benchmarked against the current most stable simulations based on the BSSN method. We show that while the length of the HR run is somewhat shorter than the equivalent BSSN simulation, the HR technique improves the overall quality of the simulation, not only regarding the satisfaction of the Hamiltonian constraint, but also the behaviour of the total angular momentum of the binary. The latest quantity agrees well with post-Newtonian estimations for point-mass binaries in circular orbits. PACS numbers: 04.30.Db, 04.25.Dm, 97.80.Fk
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