  Neutron star binaries and their associated gravitational wave signal
facilitate precision tests of General Relativity. Any deviation of the detected
gravitational waveform from General Relativity would therefore be a smoking gun
signature of new physics, in the form of additional forces, dark matter
particles, or extra gravitational degrees of freedom. To be able to probe new
theories, precise knowledge of the expected waveform is required. In our work,
we consider a generic setup by augmenting General Relativity with an
additional, massive scalar field. We then compute the inspiral dynamics of a
binary system by employing an effective field theoretical approach, while
giving a detailed introduction to the computational framework. Finally, we
derive the modified gravitational waveform at next-to-leading order. As a
consequence of our model-agnostic approach, our results are readily adaptable
to a plethora of new physics scenarios, including modified gravity theories and
scalar dark matter models.
