Could PBHs and secondary GWs have originated from squeezed initial states?

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[Abridged] Recently, the production of primordial black holes (PBHs) and secondary gravitational waves (GWs) due to enhanced scalar power on small scales have garnered considerable attention in the literature.

• Often, the mechanism considered to arrive at such enhanced power involves a modification of the standard slow roll inflationary dynamics, achieved with the aid of fine-tuned potentials.
• In this work, we investigate another well known method to generate features in the power spectrum wherein the initial state of the perturbations is assumed to be squeezed states.
• This approach is technically straightforward to implement since the Bogoliubov coefficients characterizing the squeezed initial states, can be immediately determined from the desired form of the power spectrum.