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Semiclassical realization of infrared renormalons
1Physics Department, University of Cincinnati, Ohio 45221, USA.
Physical Review Letters
|September 26, 2012
Summary
Quantum field theory (QFT) perturbation series ambiguities are resolved by identifying bion-antibion events. These events correspond to novel saddle point configurations, offering a semiclassical realization for elusive renormalons in gauge theories.
Area of Science:
- Theoretical Physics
- Quantum Field Theory
- High Energy Physics
Background:
- Perturbation series in quantum field theory (QFT) are typically divergent and not Borel resummable due to ambiguities from singularities.
- In quantum mechanics, these ambiguities can be resolved by instanton-anti-instanton events, but this mechanism fails in asymptotically free gauge theories.
- Singularities closer to the origin in the Borel plane, known as IR renormalon poles, lack a semiclassical realization in four dimensions.
Purpose of the Study:
- To identify the semiclassical origin of IR renormalon poles in asymptotically free gauge theories.
- To resolve the ambiguities in perturbation theory by finding corresponding saddle point configurations.
- To extend the understanding of non-perturbative effects in quantum field theory.
Main Methods:
- Utilizing continuity on R(3) × S(1) to bridge between different theoretical frameworks.
- Generalizing the methods of Bogomolny and Zinn-Justin to quantum field theory.
- Identifying saddle point field configurations, specifically bion-antibion events, as potential explanations for Borel plane singularities.
Main Results:
- Identified bion-antibion events as saddle point configurations in quantum field theory.
- These bion-antibion events correspond to singularities in the Borel plane significantly closer to the origin than instanton-anti-instanton singularities.
- Established a connection between these novel configurations and the leading singularities in the Borel plane.
Conclusions:
- Bion-antibion events provide a semiclassical realization for the IR renormalon poles in the weak coupling regime of gauge theories.
- The identified saddle point configurations resolve the ambiguities in perturbation theory, offering a path towards resumming divergent series.
- This work offers new insights into the non-perturbative structure of quantum field theory and the nature of renormalons.
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