Triangle Seminars
Thursday, 9 Apr 2020
Integrable sigma models and RG flow
Nat Levine
(Imperial College)
Abstract:
It is often suggested that integrable 2d sigma models should be renormalizable, however this relationship has only previously been checked in the 1-loop approximation. The aim of this work is to understand what happens beyond 1-loop.
We shall pedagogically introduce the lambda- and eta-models, and non-abelian duality. Based on these examples, we confirm that classically integrable sigma models appear to be 2-loop renormalizable if supplemented with a particular choice of finite counterterms, i.e. quantum corrections to the target space geometry. The 2-loop beta-function of the lambda-model is computed, matching the known results for groups and symmetric spaces in the limit when the lambda-model becomes the corresponding non-abelian dual model. This leads to the statement that non-abelian duality commutes with the RG flow beyond 1-loop order.
NOTE: Please register to the mailing list at integrability-london.weebly.com to receive the link for the Zoom meeting.
It is often suggested that integrable 2d sigma models should be renormalizable, however this relationship has only previously been checked in the 1-loop approximation. The aim of this work is to understand what happens beyond 1-loop.
We shall pedagogically introduce the lambda- and eta-models, and non-abelian duality. Based on these examples, we confirm that classically integrable sigma models appear to be 2-loop renormalizable if supplemented with a particular choice of finite counterterms, i.e. quantum corrections to the target space geometry. The 2-loop beta-function of the lambda-model is computed, matching the known results for groups and symmetric spaces in the limit when the lambda-model becomes the corresponding non-abelian dual model. This leads to the statement that non-abelian duality commutes with the RG flow beyond 1-loop order.
NOTE: Please register to the mailing list at integrability-london.weebly.com to receive the link for the Zoom meeting.
Posted by: andrea