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arXiv · 2309.05244

The cosmological collider signal in the non-BD initial states

Yuan Yin
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Abstract

We investigate the cosmological collider (CC) signal arising from the tree-level exchange of a scalar spectator particle with a non-Bunch Davies (BD) initial state. We decompose the inflaton correlators into seed integrals, which we compute analytically by solving the bootstrap equations. We show that the non-BD initial state eliminates the Hubble scale Boltzmann suppression $e^{-\pi m /H}$ that usually affects the CC signal. Consequently, in this scenario, the CC can probe an energy scale much higher than the inflationary Hubble scale $H$.

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Yuan Yin. 2023-09-11. The cosmological collider signal in the non-BD initial states. https://arxiv.org/abs/2309.05244

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