Fundamental theoretical bias in gravitational wave astrophysics and the parametrized post-Einsteinian framework

• DOI: 10.1103/physrevd.80.122003
• Publication Date: 2009-12-15T15:23:06Z
• Authors: Nicolás Yunes; Frans Pretorius
• Keywords: High Energy Physics - Theory; High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics - Theory (hep-th); Astrophysics of Galaxies (astro-ph.GA); 0103 physical sciences; FOS: Physical sciences; General Relativity and Quantum Cosmology (gr-qc); Astrophysics - High Energy Astrophysical Phenomena; Astrophysics - Astrophysics of Galaxies; 01 natural sciences; General Relativity and Quantum Cosmology

We consider the concept of fundamental bias in gravitational wave astrophysics as the assumption that general relativity is the correct theory of gravity during the entire wave-generation and propagation regime. Such an assumption is valid in the weak field, as verified by precision experiments and observations, but it need not hold in the dynamical strong-field regime where tests are lacking. Fundamental bias can cause systematic errors in the detection and parameter estimation of signals, which can lead to a mischaracterization of the universe through incorrect inferences about source event rates and populations. We propose a remedy through the introduction of the parameterized post-Einsteinian framework, which consists of the enhancement of waveform templates via the inclusion of post-Einsteinian parameters. These parameters would ostensibly be designed to interpolate between templates constructed in general relativity and well-motivated alternative theories of gravity, and also include extrapolations that follow sound theoretical principles, such as consistency with conservation laws and symmetries. As an example, we construct parameterized post-Einsteinian templates for the binary coalescence of equal-mass, non-spinning compact objects in a quasi-circular inspiral. The parametrized post-Einsteinian framework should allow matched filtered data to select a specific set of post-Einsteinian parameters without a priori assuming the validity of the former, thus either verifying general relativity or pointing to possible dynamical strong-field deviations.<br/>25 pages, replaced with version accepted for publication in Phys. Rev. D<br/>