A catalogue of insights from the fourth LIGO–Virgo–KAGRA observing run

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Abbott, R. et al. GWTC-3: compact binary coalescences observed by LIGO and Virgo during the second part of the third observing run. Phys. Rev. X 13, 041039 https://doi.org/10.1103/PhysRevX.13.041039 (2023).

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Abac, A. G. et al. GWTC-4.0: searches for gravitational-wave lensing signatures. Preprint at https://doi.org/10.48550/arXiv.2512.16347 (2025).

Cheung, M.H.-Y. et al. The diffraction-lensing interpretation of GW231123 with astrophysical priors. Preprint at https://doi.org/10.48550/arXiv.2607.21834 (2026).

Abac, A. G. et al. GW250114: testing Hawking’s area law and the Kerr nature of black holes. Phys. Rev. Lett. 135, 111403 https://doi.org/10.1103/kw5g-d732 (2025).

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Abac, A. G. et al. GW241011 and GW241110: exploring binary formation and fundamental physics with asymmetric, high-spin black hole coalescences. Astrophys. J. Lett. 993, 21 https://doi.org/10.3847/2041-8213/ae0d54 (2025).

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Abac, A. G. et al. GWTC-5.0: constraints on the cosmic expansion rate and modified gravitational-wave propagation. Preprint at https://doi.org/10.48550/arXiv.2605.27227 (2026).

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Abbott, R. et al. Population of merging compact binaries inferred using gravitational waves through GWTC-3. Phys. Rev. X 13, 011048 https://doi.org/10.1103/PhysRevX.13.011048 (2023).

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Li, Y.-J., Wang, Y.-Z., Tang, S.-P. & Fan, Y.-Z. Resolving the stellar-collapse and hierarchical-merger origins of the coalescing black holes. Phys. Rev. Lett. 133, 051401 https://doi.org/10.1103/PhysRevLett.133.051401 (2024).

Antonini, F. et al. Gravitational-wave constraints on the pair-instability mass gap and nuclear burning in massive stars. Nat. Astron. 10, 1049–1056 https://doi.org/10.1038/s41550-026-02847-0 (2026).

Plunkett, C., Vitale, S., Callister, T. & Zevin, M. Signatures of a subpopulation of hierarchical mergers in the GWTC-4 gravitational-wave dataset. Phys. Rev. Lett. 137, 021404 https://doi.org/10.1103/n6p4-ftgq (2026).

Banagiri, S., Thrane, E. & Lasky, P. D. Evidence for three subpopulations of merging binary black holes at different primary masses. Phys. Rev. Lett. 137, 021403 https://doi.org/10.1103/blyb-lqv6 (2026).

Flanagan, E. et al. Distinct spin properties and astrophysical origin of low mass binary black holes in gravitational wave data. Preprint at https://doi.org/10.48550/arXiv.2607.00565 (2026).

Guttman, N., Lasky, P. D. & Thrane, E. Revealing four subpopulations of binary black-hole mergers with the Fifth Gravitational-Wave Transient Catalog. Preprint at https://doi.org/10.48550/arXiv.2607.22011 (2026).

Farah, A. M., Vijaykumar, A. & Fishbach, M. The steep redshift evolution of the hierarchical binary black hole merger rate may cause the z − χ eff correlation. Astrophys. J. Lett. 1001, 40 https://doi.org/10.3847/2041-8213/ae4e19 (2026).

Li, Y.-J., Wang, Y.-Z., Tang, S.-P. & Fan, Y.-Z. Smoking-gun evidence for hierarchical black-hole mergers. Preprint at https://doi.org/10.48550/arXiv.2607.01121 (2026).

Ivezić, Ž et al. LSST: from science drivers to reference design and anticipated data products. Astrophys. J. 873, 111 https://doi.org/10.3847/1538-4357/ab042c (2019).