2021/04/30 by Mercedes Martín-Benito, Rita B. Neves, Javier Olmedo · 27 citations
Mathematics · Physics and Astronomy · #Black Holes and Theoretical Physics #Classical mechanics #Context (archaeology) #Cosmology #Cosmology and Gravitation Theories #Geometry #Inflation (cosmology) #Loop quantum cosmology #Mathematical physics #Mathematics #Noncommutative and Quantum Gravity Theories #Physics #Quantum #Quantum cosmology #Quantum gravity #Quantum mechanics #Scalar (mathematics) #Scalar field #Spectral density #Statistics #Theoretical physics #Vacuum energy #gr-qc
paper · pdf · doi:10.1103/physrevd.103.123524
published in Physical review. D/Physical review. D. 103(12) (American Physical Society) · 10 pages, 3 figures, v2: matches published version
openalex created_date 2021/04/13 · openalex publication_date 2021/06/09 · arxiv created 2021/06/10 · arxiv updated 2021/06/11 · openalex updated_date 2026/08/05
In generic Friedmann-Lema\\itre-Robertson-Walker spacetimes, states of low energy (SLEs) are defined to minimize the regularized energy density smeared along the timelike curve of an isotropic observer, which is specified via a smearing function. For every smearing function, SLEs are unique (up to a phase) and are shown to be exact Hadamard states. In this work, we investigate the viability of SLEs as the vacuum for cosmological perturbations in hybrid loop quantum cosmology, motivated by the fact that SLEs have been shown to provide suitable vacua in models where a period of kinetic dominance precedes inflation. We find that there are two classes of smearing functions that can be seen as natural choices within this context, for which the corresponding SLEs and the resulting power spectra at the end of inflation are quite insensitive to the exact shape and support of the smearing function. Furthermore, a preliminary analysis of the tensor-to-scalar ratio and of the spectral index indicates as good an agreement with observations as that of standard cosmology.