# Singularities and Quantum Gravity

@article{Bojowald2007SingularitiesAQ, title={Singularities and Quantum Gravity}, author={Martin Bojowald}, journal={arXiv: General Relativity and Quantum Cosmology}, year={2007} }

Although there is general agreement that a removal of classical gravitational singularities is not only a crucial conceptual test of any approach to quantum gravity but also a prerequisite for any fundamental theory, the precise criteria for non-singular behavior are often unclear or controversial. Often, only special types of singularities such as the curvature singularities found in isotropic cosmological models are discussed and it is far from clear what this implies for the very general…

## 73 Citations

### 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.

### Space-Time Extensions in Quantum Gravity

- Physics
- 2010

Space-time as described by special and general relativity is a classical object. In general relativity, it becomes dynamical, participates in the interactions between all degrees of freedom and can…

### 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,…

### Effective quantum extended spacetime of polymer Schwarzschild black hole

- PhysicsClassical and Quantum Gravity
- 2019

The physical interpretation and eventual fate of gravitational singularities in a theory surpassing classical general relativity are puzzling questions that have generated a great deal of interest…

### Chapter 8 Space-Time Extensions in Quantum Gravity

- Physics
- 2010

Space-time as described by special and general relativity is a classical object. In general relativity, it becomes dynamical, participates in the interactions between all degrees of freedom and can…

### Lemaitre-Tolman-Bondi collapse from the perspective of loop quantum gravity

- Physics
- 2008

Lemaitre-Tolman-Bondi models as specific spherically symmetric solutions of general relativity simplify in their reduced form some of the mathematical ingredients of black hole or cosmological…

### Deformed General Relativity and Effective Actions from Loop Quantum Gravity

- Physics
- 2012

Canonical methods can be used to construct effective actions from deformed covariance algebras, as implied by quantum-geometry corrections of loop quantum gravity. To this end, classical…

### Quantum nature of cosmological bounces

- Physics
- 2008

Several examples are known where quantum gravity effects resolve the classical big bang singularity by a bounce. The most detailed analysis has probably occurred for loop quantum cosmology of…

### Lemaître, the Big Bang and the Quantum Universe

- Physics
- 2012

Lemaitre’s work on the geometric nature of singularities and his speculations concerning the applications of quantum physics to cosmology are confronted with later achievements in these fields. His…

### Mathematical Structure of Loop Quantum Cosmology: Homogeneous Models

- Mathematics
- 2013

The mathematical structure of homogeneous loop quantum cosmology is analyzed, starting with and taking into account the general classification of homogeneous connections not restricted to be Abelian.…

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