2009/12/31 by Sebastiano Bernuzzi, David Hilditch · 7 citations
Chemistry · Mathematics · Physics and Astronomy · #Applied mathematics #Chemistry #Conformal map #Constraint (computer-aided design) #Decomposition #Geometry #Magnetic confinement fusion research #Mathematical analysis #Mathematical optimization #Mathematics #Numerical methods for differential equations #Physics #Pulsars and Gravitational Waves Research #Statistical physics #gr-qc
paper · pdf · doi:10.1103/physrevd.81.084003
published as Phys.Rev.D81:084003,2010 · Published in PRD
openalex publication_date 2010/04/01 · arxiv created 2010/04/27 · arxiv updated 2010/04/29 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We compare numerical evolutions performed with the BSSNOK formulation and a conformal decomposition of a Z4-like formulation of general relativity. The important difference between the two formulations is that the Z4 formulation has a propagating Hamiltonian constraint, whereas BSSNOK has a zero-speed characteristic variable in the constraint subsystem. In spherical symmetry we evolve both puncture and neutron star initial data. We demonstrate that the propagating nature of the Z4 constraints leads to results that compare favorably with BSSNOK evolutions, especially when matter is present in the spacetime. From the point of view of implementation the new system is a simple modification of BSSNOK.