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arXiv · 2408.13159

Diagram dependance of the $\mathbb{CP}(1)$ beta function

Kasra Kiaee·Alexander Monin
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Abstract

We revisit the computation of the beta function in the two-dimensional $\mathbb{CP}(1)$ sigma model. We show that in different schemes, different diagrams are responsible for the running, such as momentum-independent tadpoles or even UV-finite bubble diagrams. We also comment on the relation between the beta functions and the energy dependence of scattering amplitudes.

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Kasra Kiaee, Alexander Monin. 2024-08-23. Diagram dependance of the $\mathbb{CP}(1)$ beta function. https://arxiv.org/abs/2408.13159

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