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arXiv · 1612.02075

CP(N) sigma model on a finite interval revisited

A. Milekhin
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Abstract

In this short note we will revisit the large $N$ solution of $\mathbb{C}P^N$ sigma model on a finite interval of length $L$. We will find a family of boundary conditions for which the large $N$ saddle point can be found analytically. For a certain choice of the boundary conditions the theory has only one phase for all values of $L$. Also, we will provide an example when there are two phases: for large $L$ there is a standard phase with an unbroken $U(1)$ gauge symmetry and for small $L$ there is Higgs phase with a broken gauge symmetry.

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A. Milekhin. 2016-12-06. CP(N) sigma model on a finite interval revisited. https://doi.org/10.1103/physrevd.95.085021

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