Effective action and linear response of compact objects in Newtonian gravity
Abstract
We apply an effective field theory method for the gravitational interaction of compact stars, developed within the context of general relativity, to Newtonian gravity. In this effective theory a compact object is represented by a point particle possessing generic gravitational multipole moments. The time evolution of the multipoles depends on excitations due to external fields. This can formally be described by a response function of the multipoles to applied fields. The poles of this response correspond to the normal oscillation modes of the star. This gives rise to resonances between modes and tidal forces in binary systems. The connection to the standard formalism for tidal interactions and resonances in Newtonian gravity is worked out. Our approach can be applied to more complicated situations. In particular, a generalization to general relativity is possible.
Cite
@article{arxiv.1306.5820,
title = {Effective action and linear response of compact objects in Newtonian gravity},
author = {Sayan Chakrabarti and Térence Delsate and Jan Steinhoff},
journal= {arXiv preprint arXiv:1306.5820},
year = {2013}
}
Comments
RevTeX, 19 pages, 1 figure, 1 table, relativistic generalization in arXiv:1304.2228 [gr-qc]. v2: minor corrections and additions, v3: published version