# Approximating the physical inner product of Loop Quantum Cosmology

@article{Bahr2006ApproximatingTP, title={Approximating the physical inner product of Loop Quantum Cosmology}, author={Benjamin Bahr and Thomas Thiemann}, journal={Classical and Quantum Gravity}, year={2006}, volume={24}, pages={2109-2138} }

In this paper, we investigate the possibility of approximating the physical inner product of constrained quantum theories. In particular, we calculate the physical inner product of a simple cosmological model in two ways: firstly, we compute it analytically via a trick; secondly, we use the complexifier coherent states to approximate the physical inner product defined by the master constraint of the system. We find that the approximation is able to recover the analytic solution of the problem…

## 10 Citations

Relating loop quantum cosmology to loop quantum gravity: symmetric sectors and embeddings

- Physics
- 2007

In this paper we address the meaning of states in loop quantum cosmology (LQC), in the context of loop quantum gravity. First, we introduce a rigorous formulation of an embedding proposed by Bojowald…

Physical time and other conceptual issues of quantum gravity on the example of loop quantum cosmology

- Physics
- 2009

Several conceptual aspects of quantum gravity (QG) are studied on the example of the homogeneous isotropic loop quantum cosmology (LQC) model. In particular: (i) the proper time of the comoving…

Diffeomorphism invariant cosmological sector in loop quantum gravity

- Physics
- 2017

In this paper we work out in detail a new proposal to define rigorously a sector of loop quantum gravity at the diffeomorphism invariant level corresponding to homogeneous and isotropic cosmologies,…

Loop Quantum Cosmology

- PhysicsLiving reviews in relativity
- 2005

Quantum gravity is expected to be necessary in order to understand situations where classical general relativity breaks down. In particular in cosmology one has to deal with initial singularities,…

The flat FRW model in LQC: self-adjointness

- Physics
- 2008

The flat Friedman?Robertson?Walker (FRW) model coupled to the massless scalar field according to the improved, background scale-independent version of Ashtekar, Paw?owski and Singh [1] is considered.…

Loop Quantum Cosmology

- PhysicsLiving reviews in relativity
- 2008

L loop quantum cosmology is an application of loop quantum gravity to homogeneous systems, which removes classical singularities and introduces the main effects of quantum effects into effective classical equations, which allow one to avoid the interpretational problems of quantum theory.

A dynamical metric and its ground state from the breaking down of the topological invariance of the Euler characteristic

- PhysicsThe European Physical Journal C
- 2019

Quantum state wave functionals are constructed in exact form for the graviton-like field theory obtained by breaking down the topological symmetry of the string action related with the Euler…

Coherent states for FLRW space-times in loop quantum gravity

- Physics
- 2011

We construct a class of coherent spin-network states that capture properties of curved space-times of the Friedmann-Lamaitre-Robertson-Walker type on which they are peaked. The data coded by a…

Physical time and other conceptual issues of QG on the example of LQC

- Physics
- 2008

Several conceptual aspects of quantum gravity are studied on the example of the homogeneous isotropic LQC model. In particular: $(i)$ The proper time of the co-moving observers is showed to be a…

Holonomy-flux spinfoam amplitude

- Physics
- 2012

We introduce a holomorphic representation for the Lorentzian EPRL spinfoam on arbitrary 2-complexes. The representation is obtained via the Ashtekar-Lewandowski-Marolf-Mour\~ao-Thiemann heat kernel…

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