# Avoidance of singularities in asymptotically safe Quantum Einstein Gravity

## Abstract

New general spherically symmetric solutions have been derived with a cosmological “constant” Λ as a source. This Λ term is not constant but it satisfies the properties of the asymptotically safe gravity at the ultraviolet fixed point. The importance of these solutions comes from the fact that they may describe the near to the centre region of black hole spacetimes as this is modified by the Renormalization Group scaling behaviour of the fields. The consistent set of field equations which respect the Bianchi identities is derived and solved. One of the solutions (with conventional sign of temporal-radial metric components) is timelike geodesically complete, and although there is still a curvature divergent origin, this is never approachable by an infalling massive particle which is reflected at a finite distance due to the repulsive origin. Another family of solutions (of both signatures) range from a finite radius outwards, they cannot be extended to the centre of spherical symmetry, and the curvature invariants are finite at the minimum radius.

- Authors:

- Research Group of Geometry, Dynamical Systems and Cosmology,Department of Information and Communication Systems Engineering,University of the Aegean, Karlovassi 83200, Samos (Greece)
- Department of Electrical Engineering, Theory Division, ATEI of Central Greece,35100 Lamia (Greece)
- (Greece)

- Publication Date:

- Sponsoring Org.:
- SCOAP3, CERN, Geneva (Switzerland)

- OSTI Identifier:
- 22458400

- Resource Type:
- Journal Article

- Resource Relation:
- Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 10; Other Information: PUBLISHER-ID: JCAP10(2015)069; OAI: oai:repo.scoap3.org:12491; Article funded by SCOAP3. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 License. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.; Country of input: International Atomic Energy Agency (IAEA)

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BLACK HOLES; FIELD EQUATIONS; GRAVITATION; GRAVITATIONAL FIELDS; MATHEMATICAL SOLUTIONS; QUANTUM GRAVITY; RENORMALIZATION; SINGULARITY; SPACE-TIME; SPHERICAL CONFIGURATION; SYMMETRY; ULTRAVIOLET RADIATION

### Citation Formats

```
Kofinas, Georgios, Zarikas, Vasilios, and Department of Physics, Aristotle University of Thessaloniki,54124 Thessaloniki.
```*Avoidance of singularities in asymptotically safe Quantum Einstein Gravity*. United States: N. p., 2015.
Web. doi:10.1088/1475-7516/2015/10/069.

```
Kofinas, Georgios, Zarikas, Vasilios, & Department of Physics, Aristotle University of Thessaloniki,54124 Thessaloniki.
```*Avoidance of singularities in asymptotically safe Quantum Einstein Gravity*. United States. doi:10.1088/1475-7516/2015/10/069.

```
Kofinas, Georgios, Zarikas, Vasilios, and Department of Physics, Aristotle University of Thessaloniki,54124 Thessaloniki. Fri .
"Avoidance of singularities in asymptotically safe Quantum Einstein Gravity". United States.
doi:10.1088/1475-7516/2015/10/069.
```

```
@article{osti_22458400,
```

title = {Avoidance of singularities in asymptotically safe Quantum Einstein Gravity},

author = {Kofinas, Georgios and Zarikas, Vasilios and Department of Physics, Aristotle University of Thessaloniki,54124 Thessaloniki},

abstractNote = {New general spherically symmetric solutions have been derived with a cosmological “constant” Λ as a source. This Λ term is not constant but it satisfies the properties of the asymptotically safe gravity at the ultraviolet fixed point. The importance of these solutions comes from the fact that they may describe the near to the centre region of black hole spacetimes as this is modified by the Renormalization Group scaling behaviour of the fields. The consistent set of field equations which respect the Bianchi identities is derived and solved. One of the solutions (with conventional sign of temporal-radial metric components) is timelike geodesically complete, and although there is still a curvature divergent origin, this is never approachable by an infalling massive particle which is reflected at a finite distance due to the repulsive origin. Another family of solutions (of both signatures) range from a finite radius outwards, they cannot be extended to the centre of spherical symmetry, and the curvature invariants are finite at the minimum radius.},

doi = {10.1088/1475-7516/2015/10/069},

journal = {Journal of Cosmology and Astroparticle Physics},

number = 10,

volume = 2015,

place = {United States},

year = {Fri Oct 30 00:00:00 EDT 2015},

month = {Fri Oct 30 00:00:00 EDT 2015}

}