Pad\'e approximants for truncated post-Newtonian neutron star models

Abstract

Pad\'e approximants to truncated post-Newtonian neutron star models are constructed. The Pad\'e models converge faster to the general relativistic (GR) solution than the truncated post-Newtonian ones. The evolution of initial data using the Pad\'e models approximates better the evolution of full GR initial data than the truncated Taylor models. In the absence of full GR initial data (e.g., for neutron star binaries or black hole binary systems), Pad\'e initial data could be a better option than the straightforward truncated post-Newtonian (Taylor) initial data.Comment: 19 pages (RevTeX), 9 eps figures. Three new figures and additional discussion on 1-parameter Pad\'e expansion. Accepted for publication in Physical Review