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Novel Phase Structure of Twisted O(N) phi^4 model on M^D-1 \times S^1

Katsuhiko Ohnishi·Makoto Sakamoto
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Abstract

We study the O(N) $ϕ^4$ model compactified on $M^{D-1}\otimes S^1$, which allows to impose twisted boundary conditions for the $S^1$-direction. The O(N) symmetry can be broken to $H$ explicitly by the boundary conditions and further broken to $I$ spontaneously by vacuum expectation values of the fields. The symmetries $H$ and $I$ are completely classified and the model turns out to have unexpectedly a rich phase structure. The unbroken symmetry $I$ is shown to depend on not only the boundary conditions but also the radius of $S^1$, and the symmetry breaking patterns are found to be unconventional. The spontaneous breakdown of the translational invariance is also discussed.

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Katsuhiko Ohnishi, Makoto Sakamoto. 2000-06-07. Novel Phase Structure of Twisted O(N) phi^4 model on M^D-1 \times S^1. https://doi.org/10.1016/s0370-2693(00)00724-3

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