6 papers
Regular black holes and their relationship to polymerized models and mimetic gravity
Kristina Giesel, Hongguang Liu, Parampreet Singh +1
We present further applications of the formalism introduced by the authors in arXiv:2308.10949, which allows embedding of a broad class of generalized LTB models into effective sph…
Analysing (cosmological) singularity avoidance in loop quantum gravity using U coherent states and Kummer's functions
Kristina Giesel, David Winnekens
Using a new procedure based on Kummer's Confluent Hypergeometric Functions, we investigate the question of singularity avoidance in loop quantum gravity (LQG) in the context of U$(…
Relating dust reference models to conventional systems in manifestly gauge invariant perturbation theory
Kristina Giesel, Bao-Fei Li, Parampreet Singh
Models with dust reference fields in relational formalism have proved useful in understanding the construction of gauge-invariant perturbation theory to arbitrary orders in the can…
Towards a reduced phase space quantization in loop quantum cosmology with an inflationary potential
Kristina Giesel, Bao-Fei Li, Parampreet Singh
We explore a reduced phase space quantization of loop quantum cosmology (LQC) for a spatially flat FLRW universe filled with reference fields and an inflaton field in a Starobinsky…
Mukhanov-Sasaki equation in manifestly gauge-invariant linearized cosmological perturbation theory with dust reference fields
Kristina Giesel, Laura Herold, Bao-Fei Li +1
The aim of this article is to understand the role of dust reference fields, often also called clocks, on cosmological perturbations around a flat FLRW universe. We derive the Mukha…
Dynamics of Dirac observables in canonical cosmological perturbation theory
Kristina Giesel, Parampreet Singh, David Winnekens
The relational formalism based on geometrical clocks and Dirac observables in linearized canonical cosmological perturbation theory is used to introduce an efficient method to find…