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Recursive Landau Analysis
Simon Caron-Huot1, Miguel Correia1, Mathieu Giroux1
1McGill University, Department of Physics, 3600 Rue University, Montréal, H3A 2T8 Quebec, Canada.
Physical Review Letters
|October 12, 2025
Summary
A new recursive method uses unitarity to compute Landau singularities in scattering amplitudes. This technique accelerates analytic calculations for complex Feynman diagrams, offering new predictions for the Standard Model.
Area of Science:
- High Energy Physics
- Quantum Field Theory
Background:
- Calculating Landau singularities is crucial for understanding scattering amplitudes in quantum field theory.
- Current methods face limitations in speed and applicability for complex Feynman diagrams.
Purpose of the Study:
- To develop a novel recursive method for calculating Landau singularities.
- To enable rapid analytic computations of these singularities directly in kinematic space.
Main Methods:
- The proposed method leverages the fundamental principle of unitarity.
- It applies a recursive approach to n-point scattering amplitudes.
- Calculations are performed directly in kinematic space.
Main Results:
- The method successfully computes Landau singularities for a broad range of Feynman diagrams.
- It significantly surpasses the speed and scope of existing state-of-the-art techniques.
- New predictions are generated for multi-loop processes within the Standard Model.
Conclusions:
- The recursive unitarity-based method offers a powerful tool for analytic calculations of Landau singularities.
- This advancement has significant implications for studying Standard Model processes involving massive quarks and electroweak particles.
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