Non-oscillatory power spectrum from States of Low Energy in kinetically dominated early universes

TL;DR

This paper explores how the high curvature region in Loop Quantum Cosmology affects the definition of States of Low Energy, showing that shifting the test function support yields power spectra similar to the Non-oscillatory vacuum, which is also of Hadamard type.

Contribution

It demonstrates that adjusting the support of the test function in SLEs produces primordial spectra akin to the Non-oscillatory vacuum and establishes its Hadamard nature.

Findings

Shifting test function support aligns SLE spectra with NO vacuum.

NO vacuum is proven to be of Hadamard type.

High curvature effects influence SLE definitions in LQC.

Abstract

Recently, States of Low Energy (SLEs) have been proposed as viable vacuum states of primordial perturbations within Loop Quantum Cosmology (LQC). In this work we investigate the effect of the high curvature region of LQC on the definition of SLEs. Shifting the support of the test function that defines them away from this regime results in primordial power spectra of perturbations closer to those of the so-called Non-oscillatory (NO) vacuum, which is another viable choice of initial conditions previously introduced in the LQC context. Furthermore, through a comparison with the Hadamard-like SLEs, we prove that the NO vacuum is of Hadamard type as well.