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arXiv · 2208.00075

The Physical Content of Long Tensor Modes in Cosmology

Nicola Bartolo·Giovanni Battista Carollo·Sabino Matarrese·Luigi Pilo·Rocco Rollo
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Abstract

We analyze the physical content of squeezed bispectra involving long-wavelength tensor perturbations, showing that these modes cannot be gauged away, except for the exact (unphysical) limit of infinite wavelength, $k = 0$. This result has a direct implication on the validity of the Maldacena consistency relation, respected by a subclass of inflationary models. Consequently, in the squeezed limit, as in the case of the scalar-scalar-scalar bispectrum, squeezed mixed correlators could be observed by future experiments, remaining a key channel to study Early Universe physics and discriminate among different models of inflation.

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Nicola Bartolo, Giovanni Battista Carollo, Sabino Matarrese, Luigi Pilo, Rocco Rollo. 2022-07-29. The Physical Content of Long Tensor Modes in Cosmology. https://doi.org/10.1088/1475-7516%2F2022%2F11%2F034

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