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arXiv · 1604.05630

Large-N CP(N-1) sigma model on a finite interval: physical boundary effects

Stefano Bolognesi·Kenichi Konishi·Keisuke Ohashi
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Abstract

We analyze the two-dimensional CP(N-1) sigma model defined on a finite space interval L, with various boundary conditions, in the large N limit. With the Dirichlet boundary condition at the both ends, we show that the system has a unique phase, which smoothly approaches in the large L limit the standard 2D CP(N-1) sigma model in confinement phase, with a constant mass generated for the n(i) fields. We study the full functional saddle-point equations for finite L, and solve them numerically. The latter reduces to the well-known gap equation in the large L limit. It is found that the solution satisfies actually both the Dirichlet and Neumann conditions.

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Stefano Bolognesi, Kenichi Konishi, Keisuke Ohashi. 2016-04-19. Large-N CP(N-1) sigma model on a finite interval: physical boundary effects. https://arxiv.org/abs/1604.05630

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