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arXiv · 2111.06884

Signatures of Primordial Gravitational Waves on the Large-Scale Structure of the Universe

Pritha Bari·Angelo Ricciardone·Nicola Bartolo·Daniele Bertacca·Sabino Matarrese
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Abstract

We study the generation and evolution of second-order energy-density perturbations arising from primordial gravitational waves. Such "tensor-induced scalar modes" approximately evolve as standard linear matter perturbations and may leave observable signatures in the Large-Scale Structure of the Universe. We study the imprint on the matter power-spectrum of some primordial models which predict a large gravitational-wave signal at high frequencies. This novel mechanism in principle allows us to constrain or detect primordial gravitational waves by looking at specific features in the matter or galaxy power-spectrum, thereby allowing to probe them on a range of scales unexplored so far.

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Pritha Bari, Angelo Ricciardone, Nicola Bartolo, Daniele Bertacca, Sabino Matarrese. 2021-11-12. Signatures of Primordial Gravitational Waves on the Large-Scale Structure of the Universe. https://doi.org/10.1103/physrevlett.129.091301

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