2024/12/23 by P. Lecheminant, Lecheminant, Philippe, Yuya Tanizaki +3
Physics and Astronomy · #Nonlinear Waves and Solitons #Black Holes and Theoretical Physics #Nonlinear Photonic Systems
paper · pdf · doi:10.48550/arxiv.2412.17493
A general strategy is proposed to explore the low-energy properties of two-dimensional nonlinear σ models with θ terms. We demonstrate its application to nonlinear σ models with the target space SU(N)/H, which include ℂPN-1, complex Grassmannian manifolds as well as the flag SU(N)/U(1)N-1 and SU(N))/SO(N) manifolds. By analyzing the symmetry and its anomaly content, we realize these nonlinear σ models through perturbations added to the SU(N)1 conformal field theory. For the flag-manifold SU(N)/U(1)N-1 and SU(N))/SO(N) models, those perturbations are shown to correspond to the marginal current-current operator with the specific sign which leads to a massless renormalization group flow to the SU(N)1 fixed point. In contrast, a massive regime with a two-fold ground-state degeneracy is found for the ℂPN-1 (N >2) and Grassmannian nonlinear σ models at θ=π.