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arXiv · 1612.05088

Probing the primordial universe with gravitational waves detectors

Yu-Tong Wang·Yong Cai·Zhi-Guo Liu·Yun-Song Piao
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Abstract

The spectrum of primordial gravitational waves (GWs), especially its tilt $n_T$, carries significant information about the primordial universe. Combining recent aLIGO and Planck2015+BK14 data, we find that the current limit is $n_T=0.016^{+0.614}_{-0.989}$ at 95% C.L. We also estimate the impacts of Einstein Telescope and LISA on constraining $n_T$. Moreover, based on the effective field theory of cosmological perturbations, we make an attempt to confront some models of early universe scenarios, which produce blue-tilted GWs spectrum ($n_T>0$), with the corresponding datasets.

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Yu-Tong Wang, Yong Cai, Zhi-Guo Liu, Yun-Song Piao. 2016-12-15. Probing the primordial universe with gravitational waves detectors. https://doi.org/10.1088/1475-7516%2F2017%2F01%2F010

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