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A positive-energy theorem for Einstein-aether and Hořava gravity.
David Garfinkle1, Ted Jacobson
1Department of Physics, Oakland University, Rochester, Michigan 48309, USA.
Physical Review Letters
|December 21, 2011
Summary
Energy positivity is confirmed for specific solutions in Einstein-aether theory and Hořava gravity. This finding applies to solutions with a divergence-free aether 4-vector, particularly spherically symmetric ones.
Area of Science:
- Theoretical Physics
- General Relativity
- Quantum Gravity
Background:
- Einstein-aether theory and Hořava gravity are extensions of general relativity.
- Investigating energy conditions is crucial for understanding the physical viability of gravitational theories.
Purpose of the Study:
- To establish energy positivity for a specific class of solutions in Einstein-aether theory and Hořava gravity.
- To determine the range of coupling parameters for which these solutions are physically valid.
Main Methods:
- Analysis of solutions where the aether 4-vector is divergence-free and orthogonal to a spacelike surface.
- Focus on spherically symmetric solutions at a moment of time symmetry.
Main Results:
- Energy positivity is established for the considered class of solutions.
- The result is valid within a specific range of coupling parameters.
Conclusions:
- The studied solutions in Einstein-aether theory and Hořava gravity satisfy energy positivity.
- This work contributes to the understanding of viable gravitational theories.
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