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Ultraviolet behavior of N = 8 supergravity at four loops
Z Bern1, J J M Carrasco, L J Dixon
1Department of Physics and Astronomy, UCLA, Los Angeles, California 90095-1547, USA.
Physical Review Letters
|October 2, 2009
Summary
Researchers constructed the four-loop, four-particle amplitude for N=8 supergravity. This amplitude is ultraviolet finite in four and five dimensions, suggesting potential all-orders finiteness.
Area of Science:
- Theoretical Physics
- Quantum Field Theory
- String Theory
Background:
- N=8 supergravity is a maximally extended supergravity theory with unique theoretical properties.
- Investigating the ultraviolet behavior of quantum field theories is crucial for their consistency.
Purpose of the Study:
- To construct the complete four-loop, four-particle amplitude of N=8 supergravity.
- To investigate the ultraviolet finiteness of this amplitude in various dimensions.
Main Methods:
- Perturbation theory calculations.
- Diagrammatic techniques for amplitude construction.
- Dimensional regularization methods.
Main Results:
- The complete four-loop, four-particle amplitude of N=8 supergravity was successfully constructed.
- The amplitude was shown to be ultraviolet finite in four dimensions.
- The amplitude was also found to be ultraviolet finite in five dimensions.
Conclusions:
- The ultraviolet finiteness in both four and five dimensions provides strong evidence for the all-orders ultraviolet finiteness of N=8 supergravity in four dimensions.
- These findings support the conjecture that N=8 supergravity is a finite quantum field theory.
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