Cosmological and High-Energy Physics Implications from Gravitational-Wave Background Searches in LIGO-Virgo-KAGRA’s O1–O4a Runs

@article{abac2026cosmological,
  title = {{Cosmological and High-Energy Physics Implications from Gravitational-Wave Background Searches in LIGO-Virgo-KAGRA’s O1–O4a Runs}},
  author = {Adrian Abac and I. Abouelfettouh and F. Acernese and K. Ackley and Christian Adamcewicz and S. Adhicary and D. Adhikari and N. Adhikari and R. X. Adhikari and V. K. Adkins and Samsuzzaman Afroz and A. Agapito and D. Agarwal and M. Agathos and N. Aggarwal and S. Aggarwal and O. D. Aguiar and I.-L. Ahrend and L. Aiello and A. Ain and P. Ajith and Tomotada Akutsu and Simone Albanesi and W. Ali and S. Al-Kershi and C. Alléné and A. Allocca and S. Al-Shammari and P. A. Altin and S. Álvarez-López and W. Amar and O. Amarasinghe and A. Amato and F. Amicucci and C. Amra and A. Ananyeva and S. B. Anderson and Warren G. Anderson and M. Andia and M. Ando and Marc Andrés-Carcasona and T. Andrić and J. Anglin and Stefano Ansoldi and Javier Mauricio Antelis and S. Antier and M. Aoumi and E. Z. Appavuravther and S. Appert and S. K. Apple and Koji Arai and A. Araya and M. C. Araya and M. Arca Sedda and J. S. Areeda and N. Aritomi and F. Armato and Sharon Armstrong and N. Arnaud and M. Arogeti},
  journal = {Physical Review X},
  year = {2026},
  month = jul,
  doi = {10.1103/dlfv-z6m2},
  url = {https://doi.org/10.1103/dlfv-z6m2},
  note = {CC BY},
}

TY  - JOUR
TI  - Cosmological and High-Energy Physics Implications from Gravitational-Wave Background Searches in LIGO-Virgo-KAGRA’s O1–O4a Runs
AU  - Adrian Abac
AU  - I. Abouelfettouh
AU  - F. Acernese
AU  - K. Ackley
AU  - Christian Adamcewicz
AU  - S. Adhicary
AU  - D. Adhikari
AU  - N. Adhikari
AU  - R. X. Adhikari
AU  - V. K. Adkins
AU  - Samsuzzaman Afroz
AU  - A. Agapito
AU  - D. Agarwal
AU  - M. Agathos
AU  - N. Aggarwal
AU  - S. Aggarwal
AU  - O. D. Aguiar
AU  - I.-L. Ahrend
AU  - L. Aiello
AU  - A. Ain
AU  - P. Ajith
AU  - Tomotada Akutsu
AU  - Simone Albanesi
AU  - W. Ali
AU  - S. Al-Kershi
AU  - C. Alléné
AU  - A. Allocca
AU  - S. Al-Shammari
AU  - P. A. Altin
AU  - S. Álvarez-López
AU  - W. Amar
AU  - O. Amarasinghe
AU  - A. Amato
AU  - F. Amicucci
AU  - C. Amra
AU  - A. Ananyeva
AU  - S. B. Anderson
AU  - Warren G. Anderson
AU  - M. Andia
AU  - M. Ando
AU  - Marc Andrés-Carcasona
AU  - T. Andrić
AU  - J. Anglin
AU  - Stefano Ansoldi
AU  - Javier Mauricio Antelis
AU  - S. Antier
AU  - M. Aoumi
AU  - E. Z. Appavuravther
AU  - S. Appert
AU  - S. K. Apple
AU  - Koji Arai
AU  - A. Araya
AU  - M. C. Araya
AU  - M. Arca Sedda
AU  - J. S. Areeda
AU  - N. Aritomi
AU  - F. Armato
AU  - Sharon Armstrong
AU  - N. Arnaud
AU  - M. Arogeti
PY  - 2026
DA  - 2026/07/21
JO  - Physical Review X
DO  - 10.1103/dlfv-z6m2
UR  - https://doi.org/10.1103/dlfv-z6m2
AB  - We search for gravitational-wave background signals produced by various early Universe processes in the Advanced LIGO O4a dataset, combined with the data from the earlier O1, O2, and O3 (LIGO-Virgo) runs. The absence of detectable signals enables powerful constraints on fundamental physics. We derive gravitational-wave background energy density upper limits from the O1–O4a data to constrain parameters associated with various possible processes in the early Universe: first-order phase transitions, cosmic strings, domain walls, stiff equation of state, axion inflation, second-order scalar perturbations, primordial black hole binaries, and parity violation. In our analyses, the presence of an astrophysical background produced by compact (black hole and neutron star) binary coalescences throughout the Universe is also considered. We address the implications for various cosmological and high-energy physics models based on the obtained parameter constraints. We conclude that LIGO-Virgo data already yield significant constraints on numerous early Universe scenarios.
SN  - 2160-3308
ER  -