Implications for the non-Gaussianity of primordial gravitational waves from pulsar timing arrays
Abstract
The detection of a stochastic signal by recent pulsar timing array (PTA) collaborations, including NANOGrav, PPTA, EPTA+InPTA, CPTA and MPTA, has opened a new window to explore gravitational waves (GWs) at nanohertz frequencies. Motivated by the possibility that such a signal could arise from primordial gravitational waves (PGWs), we investigate the implications of tensor non-Gaussianity for the PGW power spectrum. Utilizing PTA data sets, we provide constraints on local-type tensor non-Gaussianity parameter . We find for a log-normal PGW power spectrum. Our analysis reveals that even moderate tensor non-Gaussianity can lead to significant deviations from standard predictions, thereby offering a novel means to test inflationary scenarios and probe the underlying dynamics of the early Universe. Future multi-band GW observatories, such as LISA, Taiji, and TianQin, will be instrumental in complementing these efforts and further refining our understanding of tensor non-Gaussianity.
Keywords
Cite
@article{arxiv.2412.19196,
title = {Implications for the non-Gaussianity of primordial gravitational waves from pulsar timing arrays},
author = {Zhi-Zhang Peng and You Wu and Lang Liu},
journal= {arXiv preprint arXiv:2412.19196},
year = {2025}
}
Comments
10 pages, 2 figures, PRD accepted;