arXiv subjects

Chaoyi Yang

Publications and source records attributed to Chaoyi Yang.

3 recordsLinked to original sources

arXiv2026

Modified Teukolsky Formalism for Extreme Mass-Ratio Inspirals in Higher-Derivative Gravity

In this work, we study a model problem involving a point particle spiraling into a non-rotating black hole in higher-derivative theories of gravity. In such theories, both the background spacetime and the generation and propagation of gravitational waves differ from those in General Relativity. We develop a modified Teukolsky formalism to describe gravitational waves sourced by the point particle and, as an illustrative example, compute the resulting fluxes to the black hole horizon and null infinity for a cubic gravity theory. The formalism is constructed in a way that can be naturally extended to rotating black holes. These results represent essential steps to build extreme mass-ratio-inspiral waveforms in modified gravity theories, which may also be rescaled to approximate waveforms from comparable-mass binary black hole systems, analogous to existing approaches in General Relativity.

gr-qc↗

arXiv2026

From the Test-Mass Limit to Binary Black-Hole Waveforms in Higher-Derivative Gravity

Many higher-derivative theories predict stronger deviations from General Relativity for lower-mass black holes, while their nonlinear field equations often prevent reliable simulations of the full binary evolution. Here we develop a route from controlled black hole perturbation theory based on the modified Teukolsky formalism to comparable-mass waveforms, using parity-even cubic gravity as a representative example. We find that the tidal response of the secondary black hole enters at the same perturbative order as the direct higher-curvature correction and is therefore essential for a consistent leading-order waveform. The resulting strong-field fluxes and conservative dynamics produce an accumulated inspiral dephasing that grows toward merger. Embedding this test-mass information into an effective-one-body model, we construct inspiral-merger-ringdown waveforms for comparable-mass binaries and find coupling-dependent dephasing and waveform-peak shifts. Our results demonstrate how strong-field test-mass calculations can anchor waveform models for higher-derivative gravity when theory-specific numerical-relativity simulations are unavailable.

gr-qc↗

arXiv2026

Modeling extreme mass-ratio inspirals in astrophysical and dark-matter environments

Extreme mass-ratio inspirals offer a powerful probe of massive black holes and their environments, but interpreting their signals requires accurate models of orbital dynamics and radiation. Here we bring together advances in black-hole perturbation theory to establish a unified relativistic framework for adiabatic inspirals in perturbative astrophysical environments. Built on the modified Teukolsky formalism, the framework requires neither post-Newtonian nor slow-rotation approximations. As a first application, we calculate the leading cloud-induced corrections to gravitational-wave fluxes and conservative orbital dynamics for circular, equatorial inspirals around a rotating black hole surrounded by a synchronized ultralight scalar cloud, combining these corrections with the previously calculated scalar response. In our fiducial system, a cloud containing $10^{-4}$ of the black-hole mass produces about $-57.3$ radians of orbital dephasing over two years. The phase contributions from gravitational-wave flux corrections and background-induced orbital shifts each exceed the scalar contribution in magnitude and partially cancel, highlighting the need for coupled matter-gravity modeling. Extensible to other environments and modified gravity theories, our framework provides the relativistic inputs needed to assess detection losses and parameter biases, and to probe the nature of black-hole environments with future space-based gravitational-wave observations.

gr-qc↗