# An elementary introduction to loop quantum gravity

@article{Bodendorfer2016AnEI, title={An elementary introduction to loop quantum gravity}, author={Norbert Bodendorfer}, journal={arXiv: General Relativity and Quantum Cosmology}, year={2016} }

An introduction to loop quantum gravity is given, focussing on the fundamental aspects of the theory, different approaches to the dynamics, as well as possible future directions. It is structured in five lectures, including exercises, and requires only little prior knowledge of quantum mechanics, gauge theory, and general relativity. The main aim of these lectures is to provide non-experts with an elementary understanding of loop quantum gravity and to evaluate the state of the art of the field…

## Figures from this paper

## 36 Citations

Introduction to SU(2) recoupling theory and graphical methods for loop quantum gravity

- Physics
- 2019

We present a pedagogical introduction to SU(2) recoupling theory, focusing on those aspects of the topic which are useful for practical calculations in loop quantum gravity. In particular, we give a…

Graph coherent states for loop quantum gravity

- Physics
- 2020

In this article we further investigate the construction of graph coherent states, first introduced in [1], in the context of loop quantum gravity. We specifically investigate the possibility of…

Renormalization of group field theories for quantum gravity: new scaling results and some suggestions

- Physics
- 2020

We discuss motivation and goals of renormalization analyses of group field theory models of simplicial 4d quantum gravity, and review briefly the status of this research area. We present some new…

Renormalization of Group Field Theories for Quantum Gravity: New Computations and Some Suggestions

- PhysicsFrontiers in Physics
- 2020

We discuss motivation and goals of renormalization analyses of group field theory models of simplicial 4d quantum gravity, and review briefly the status of this research area. We present some new…

Thermal representations in group field theory: squeezed vacua and quantum gravity condensates

- PhysicsJournal of High Energy Physics
- 2020

We apply the formalism of thermofield dynamics to group field theory quantum gravity and construct thermal representations associated with generalised equilibrium Gibbs states using Bogoliubov…

Protected SL(2,ℝ) symmetry in quantum cosmology

- PhysicsJournal of Cosmology and Astroparticle Physics
- 2019

The polymer quantization of cosmological backgrounds provides an alternative path to the original Wheeler-de Witt (WdW) quantum cosmology, based on a different representation the commutation…

Scalar curvature operator for models of loop quantum gravity on a cubical graph

- Mathematics, Physics
- 2021

In this article we introduce a new operator representing the three-dimensional scalar curvature in loop quantum gravity. Our construction does not apply to the entire kinematical Hilbert space of…

State refinements and coarse graining in a full theory embedding of loop quantum cosmology

- Physics
- 2016

Bridging between descriptions involving few large and many small quantum numbers is the main open problem in loop quantum gravity. In other words, one would like to be able to represent the same…

The Physical Relevance of the Fiducial Cell in Loop Quantum Cosmology

- Mathematics
- 2021

A common way to avoid divergent integrals in homogeneous spatially non-compact gravitational systems, as e.g. cosmology, is to introduce a fiducial cell by cutting-off the spatial slice at a finite…

Inequivalent coherent state representations in group field theory

- Mathematics
- 2017

In this paper we propose an algebraic formulation of group field theory and consider non-Fock representations based on coherent states. We show that we can construct representations with an infinite…

## References

SHOWING 1-10 OF 283 REFERENCES

Introduction to loop quantum gravity

- Physics
- 2012

Loop quantum gravity is an attempt to formulate a quantum theory of general relativity. The quantisation is performed in a mathematically rigorous, non-perturbative and background independent manner…

Loop quantum gravity: an outside view

- Physics
- 2005

We review aspects of loop quantum gravity in a pedagogical manner, with the aim of enabling a precise but critical assessment of its achievements so far. We emphasize that the off-shell (‘strong’)…

An Introduction to Loop Quantum Gravity Through Cosmology

- Physics
- 2007

This introductory review is addressed to beginning researchers. Some of the distinguishing features of loop quantum gravity are illustrated through loop quantum cosmology of FRW models. In…

Towards loop quantum gravity without the time gauge.

- PhysicsPhysical review letters
- 2009

The Hamiltonian formulation of the Holst action is reviewed and it provides a solution of second-class constraints corresponding to a generic local Lorentz frame that emphasizes that the loop quantum gravity quantization procedure can be applied when the time-gauge condition does not stand.

Some conceptual issues in loop quantum cosmology

- Physics
- 2016

Loop quantum gravity is a mature theory. To proceed to explicit calculations in cosmology, it is necessary to make assumptions and simplifications based on the symmetries of the cosmological setting.…

Conceptual issues in loop quantum cosmology

- Physics
- 2016

Loop quantum gravity is a mature theory. To proceed to explicit calculations in cosmology, it is necessary to make assumptions and simplifications based on the symmetries of the cosmological setting.…

Zakopane lectures on loop gravity

- Physics
- 2011

This is a first version of the introductory lectures on loop quantum gravity that I will give at the quantum gravity school in Zakopane. The theory is presented in self-contained form, without…

Covariant Loop Quantum Gravity: An Elementary Introduction to Quantum Gravity and Spinfoam Theory

- Physics
- 2014

Preface Part I. Foundations: 1. Spacetime as a quantum object 2. Physics without time 3. Gravity 4. Classical discretization Part II. The 3D Theory: 5. 3D Euclidean theory 6. Bubbles and cosmological…

Introduction to loop quantum gravity and spin foams

- Physics
- 2004

These notes are a didactic overview of the non perturbative and background independent approach to a quantum theory of gravity known as loop quantum gravity. The definition of real connection…