Eccentric Binary Black Holes: From Simulation to Waveform Modelling

PJ Nee (Albert Einstein Institute)

Time:

10AM Tuesday, 11 November 2025

Location:

Beech Hill, Room C2.27

Mounting evidence indicates that some of the gravitational wave signals detected by the LIGO/Virgo/KAGRA observatories might arise from eccentric compact object binaries, underscoring the need for accurate waveform models for such systems. Numerical relativity, where one simulates the full theory of general relativity using supercomputers, serves as the gold standard in terms of predictions for binary black hole systems, typically serving as the "ground truth" for validating other, approximate waveform models.

In this seminar, I will discuss recent progress in modelling eccentric binary black hole systems using numerical relativity. First, I will present new approaches to systematically probing the parameter space with numerical relativity simulations. This approach, which relies on comparisons of gauge-invariant quantities with state-of-the-art analytic predictions, yields unprecedented control over both the reference parameters of the system and the simulation length. Using these simulations, I will discuss the phenomenology of eccentric mergers, providing a straightforward approach to incorporating eccentric mergers into modern waveform models. Finally, I will present NRSurE_q4NoSpin_22, the first numerical relativity surrogate model for eccentric binary systems that is faithful to the underlying simulations.