Robustness of the primordial power spectrum in hybrid loop quantum cosmology to approximations near the bounce
Phys. Rev. D 114, 086010 – Published 14 October, 2026
DOI: https://doi.org/10.1103/mqtj-28gv
Abstract
We prove the robustness of the analytic approximation used in (hybrid) loop quantum cosmology to compute the primordial power spectrum of the cosmological perturbations for a recently proposed vacuum state (the nonoscillatory state with asymptotic Hamiltonian diagonalization). To investigate this, we study different approximations to the effective mass of these perturbations near the bounce, showing that the Pöschl-Teller potential employed in previous works leads to indistinguishable power spectra compared to other estimations of the mass, provided that they successfully capture the characteristic scale of the bounce, which translates into a scale of power suppression.
