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Published on: November 15, 2013
Grand unification and enhanced quantum gravitational effects
Xavier Calmet1, Stephen D H Hsu, David Reeb
1Catholic University of Louvain, Center for Particle Physics and Phenomenology, 2 Chemin du Cyclotron, Louvain-la-Neuve, Belgium. xavier.calmet@uclouvain.be
Physical Review Letters
|November 13, 2008
Summary
Renormalization effects in grand unified theories can alter quantum gravity scales. Gravitational impacts may prevent coupling constant unification, even with modest effects.
Area of Science:
- Theoretical Physics
- High-Energy Physics
- Quantum Gravity
Background:
- Grand unified theories (GUTs) aim to unify fundamental forces.
- Renormalization group (RG) analyses are crucial for understanding particle physics at different energy scales.
- The interplay between quantum gravity and GUTs is not fully understood.
Purpose of the Study:
- To investigate the impact of renormalization effects on the scale of quantum gravity in GUTs.
- To analyze how gravitational higher-dimensional operators modify unification boundary conditions.
- To compare the significance of gravitational effects with standard two-loop RG corrections.
Main Methods:
- Analysis of renormalization effects in theories with a large number of fields.
- Incorporation of higher-dimensional operators induced by quantum gravity.
- Renormalization group evolution of coupling constants.
Main Results:
- Renormalization significantly modifies the scale of strong quantum gravity.
- Gravitational effects can alter boundary conditions for coupling constant unification.
- The magnitude and uncertainty of gravitational effects can exceed two-loop corrections.
- Modest gravitational effects can preclude unification in some scenarios.
Conclusions:
- Quantum gravity's influence on unification scales is substantial and often underestimated.
- Higher-dimensional operators induced by gravity play a critical role in GUTs.
- Standard RG analyses may require significant revision to include gravitational effects accurately.
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