Black-Hole Models in Loop Quantum Gravity
Abstract
:1. Introduction
2. Proposals
2.1. Basic Premise of Bounce-Based Black Holes
- (i)
- It must be possible to obtain the effect as a specific solution of a consistent set of field equations.
- (ii)
- Together with the specific solution required by (i), there must be a set of solutions related to by gauge transformations that
- (a)
- Preserve the field equations and
- (b)
- Have corresponding coordinate transformations from to such that .
- (ii.b’)
- The gauge transformations are such that their classical limit has corresponding coordinate transformations from to with .
2.2. Modifications Suggested by Loop Quantum Cosmology
2.3. Violations of General Covariance
2.3.1. Slicing Dependence
2.3.2. Spherically Symmetric Models
3. Modified Space-Time Structure
3.1. Anomaly-Freedom
3.2. Signature Change
3.3. Signature Change and Non-Singular Space-Time
3.4. Evaporation Scenarios Ruled Out by Signature Change
3.5. Evaporation Scenarios Consistent with Signature Change
3.6. Unexpected Relationships with Other Approaches
3.7. Avoiding Signature Change in Models of Loop Quantum Gravity
4. Conclusions
Funding
Conflicts of Interest
References
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Bojowald, M. Black-Hole Models in Loop Quantum Gravity. Universe 2020, 6, 125. https://doi.org/10.3390/universe6080125
Bojowald M. Black-Hole Models in Loop Quantum Gravity. Universe. 2020; 6(8):125. https://doi.org/10.3390/universe6080125
Chicago/Turabian StyleBojowald, Martin. 2020. "Black-Hole Models in Loop Quantum Gravity" Universe 6, no. 8: 125. https://doi.org/10.3390/universe6080125
APA StyleBojowald, M. (2020). Black-Hole Models in Loop Quantum Gravity. Universe, 6(8), 125. https://doi.org/10.3390/universe6080125