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Published on: November 15, 2013
Four-Loop Gauge and Three-Loop Yukawa Beta Functions in a General Renormalizable Theory
Alexander Bednyakov1,2, Andrey Pikelner1
1Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna 141980, Russia.
We calculated beta functions for gauge and Yukawa couplings in quantum field theory up to four loops. Our method uses simplified models to determine coefficients for general theories, including the Standard Model.
Area of Science:
- High-energy physics
- Quantum field theory
- Particle physics
Background:
- Beta functions describe how coupling strengths change with energy scale.
- Calculating these functions is crucial for understanding particle interactions and theory consistency.
- Previous calculations were limited in scope and loop order.
Purpose of the Study:
- To present general four-loop beta functions for gauge and Yukawa couplings.
- To develop a method for determining unknown coefficients in beta function calculations.
- To apply these results to the Standard Model and its extensions.
Main Methods:
- Developing a general ansatz for beta functions.
- Fixing unknown coefficients through direct calculations in simplified models.
- Extending calculations to four loops for gauge couplings and three loops for Yukawa couplings.
Main Results:
- Derived beta functions for gauge and Yukawa couplings in general four-dimensional quantum field theory.
- Provided expressions for four-loop gauge couplings and three-loop Yukawa couplings.
- Applied results to the Standard Model, including extensions with multiple Higgs doublets.
Conclusions:
- The presented method allows for the calculation of beta functions in complex quantum field theories.
- The results are applicable to the Standard Model and provide a basis for further theoretical investigations.
- This work advances the understanding of coupling constant evolution in fundamental physics.
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