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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Maximal R-symmetry violating amplitudes in type IIb superstring theory
1II. Institut für Theoretische Physik, Universität Hamburg, Hamburg, Germany. Rutger.Boels@desy.de
Physical Review Letters
|September 26, 2012
Summary
Researchers quantified R-symmetry violation in type IIB superstring theory amplitudes. They discovered a simple class of amplitudes that maximally violate R symmetry, impacting effective field theory contributions.
Area of Science:
- Theoretical Physics
- String Theory
- Quantum Field Theory
Background:
- Type IIB superstring theory is a leading candidate for a quantum theory of gravity.
- Understanding R-symmetry violation is crucial for probing string theory in flat backgrounds.
- Effective field theory contributions reveal low-energy physics of string theories.
Purpose of the Study:
- To quantify R-symmetry violation in type IIB superstring theory amplitudes.
- To identify and characterize a simple class of non-vanishing amplitudes violating R symmetry maximally.
- To determine the first three effective field theory contributions at string tree level.
Main Methods:
- Utilizing on-shell superspace techniques.
- Analyzing type IIB superstring theory amplitudes in a 10-dimensional flat background.
- Establishing general properties and extensions of the identified amplitude class.
Main Results:
- Demonstrated the existence of a simple class of amplitudes that maximally violate R symmetry.
- Showed that these amplitudes determine the first three nontrivial effective field theory contributions at string tree level.
- Conjectured the exact analytic part of the first two of these contributions.
Conclusions:
- The identified class of amplitudes provides a powerful tool for studying R-symmetry violation.
- These findings offer insights into the structure of type IIB superstring theory and its low-energy predictions.
- The results pave the way for further investigations into higher-order effective field theory corrections.
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