Work

Polar perturbations in Kantowski-Sachs spacetimes and hybrid quantum cosmology

Year: 2025

Type: article

Abstract: Increasing attention has been recently devoted to the study of Kantowski-Sachs spacetime as a way to explore the interior of a Schwarzschild black hole. In this work, we construct a Hamiltonian formulation for polar perturbations of this spacetime in the presence of a perturbative massless scalar field. Our analysis is based on a truncated action at quadratic order in perturbations. Both background and perturbative degrees of freedom are treated dynamically, forming a combined system that is endowed with the canonical structure obtained from our truncated action. First-order perturbations of the metric and the matter field are described using perturbative gauge invariants, linear perturbative constraints, and their corresponding canonical variables. For the quantum description, we adopt a hybrid approach where the background is quantized with loop quantum gravity techniques and the perturbations with conventional quantum field methods.

Source: Physical review. D/Physical review. D.

DOI: 10.1103/physrevd.111.086024

Authors: Guillermo A. Mena Marugán, Andrés Mínguez-Sánchez

Institutions: Consejo Superior de Investigaciones Científicas, Instituto de Estructura de la Materia

Language: English

Topic: Noncommutative and Quantum Gravity Theories

Subfield: Statistical and Nonlinear Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: Comunidad de Madrid, Ministerio de Ciencia e Innovación, Consejo Superior de Investigaciones Científicas, Agencia Estatal de Investigación

Awards: G4210166958, G4923285465, G513744768