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arXiv · 2305.08071

On the Decoherence of Primordial Gravitons

Sirui Ning·Chon Man Sou·Yi Wang
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Abstract

It is well-known that the primordial scalar curvature and tensor perturbations, $\zeta$ and $\gamma_{ij}$, are conserved on super-horizon scales in minimal inflation models. However, their wave functional has a rapidly oscillating phase which is slow-roll unsuppressed, as can be seen either from boundary (total-derivative) terms of cosmological perturbations, or the WKB approximation of the Wheeler-DeWitt equation. Such an oscillatory phase involves gravitational non-linearity between scalar and tensor perturbations. By tracing out unobserved modes, the oscillatory phase causes faster decoherence of primordial gravitons compared to those by bulk interactions. Our results put a stronger lower bound of decoherence effect to the recent proposals probing squeezed primordial gravitons.

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Sirui Ning, Chon Man Sou, Yi Wang. 2023-05-14. On the Decoherence of Primordial Gravitons. https://doi.org/10.1007/jhep06(2023)101

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