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Modern gravitational-wave science demands increasingly accurate and computationally intensive numerical relativity (NR) simulations. The Python-based, open-sourceNRPyframework generates optimized C/C++ code for NR, including the complete NR codeBlackHoles@Home(BH@H), which leverages curvilinear coordinates well-suited to many astrophysical scenarios. Historically,BH@Hwas limited to single-nodeOpenMPCPU parallelism. To address this, we introducesuperB, an open-source extension toNRPythat enables automatic generation of scalable, task-based, distributed-memoryCharm++code from existingBH@Hmodules. The generated code partitions the structured grids used byNRPy/BH@H, managing communication between them. Its correctness is validated through bit-identical results with the standardOpenMPversion on a single node and via a head-on binary black hole simulation in cylindrical-like coordinates, accurately reproducing quasi-normal modes (up to ). ThesuperB/NRPy-generated code demonstrates excellent strong scaling, achieving an ≈45× speedup on 64 nodes (7168 cores) compared to the original single-nodeOpenMPcode for a large 3D vacuum test. This scalable infrastructure benefits demanding simulations and lays the groundwork for future multi-patch grid support, targeting long inspirals, extreme parameter studies, and rapid follow-ups. This infrastructure readily integrates with otherNRPy/BH@H-based projects, enabling performant scaling for the general relativistic hydrodynamics codeGRoovy, and facilitating future coupling with GPU acceleration via theNRPy-CUDAproject.
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Simulating binary black hole mergers using discontinuous Galerkin methods
Abstract Binary black holes are the most abundant source of gravitational-wave observations. Gravitational-wave observatories in the next decade will require tremendous increases in the accuracy of numerical waveforms modeling binary black holes, compared to today’s state of the art. One approach to achieving the required accuracy is using spectral-type methods that scale to many processors. Using theSpECTREnumerical-relativity (NR) code, we present the first simulations of a binary black hole inspiral, merger, and ringdown using discontinuous Galerkin (DG) methods. The efficiency of DG methods allows us to evolve the binary through ∼ 18 orbits at reasonable computational cost. We then useSpECTRE’s Cauchy Characteristic Evolution (CCE) code to extract the gravitational waves at future null infinity. The open-source nature ofSpECTREmeans this is the first time a spectral-type method for simulating binary black hole evolutions is available to the entire NR community.
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- PAR ID:
- 10589187
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- IOP
- Date Published:
- Journal Name:
- Classical and Quantum Gravity
- Volume:
- 42
- Issue:
- 3
- ISSN:
- 0264-9381
- Page Range / eLocation ID:
- 035001
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1088/1361-6382/ad9f19
