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arXiv · hep-lat/9612004

A Strong-Coupling Analysis of the Lattice $CP^{N-1}$ Models in the Presence of a $θ$ Term

Jan Plefka·Stuart Samuel
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Abstract

A $θ$ term, which couples to topological charge, is added to the lattice $CP^{N-1}$ model. The strong-coupling character expansion is developed. The series for the free energy and mass gap are respectively computed to tenth order and fourth order. Several features of the strong-coupling analysis emerge. One is the loss of superconfinement. Another is that in the intermediate coupling constant region, there are indications of a transition to a deconfining phase when $θ$ is sufficiently large. The transition is like the one which has been observed in Monte Carlo simulations of a similar lattice $CP^{N-1}$ action.

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Jan Plefka, Stuart Samuel. 1996-12-05. A Strong-Coupling Analysis of the Lattice $CP^{N-1}$ Models in the Presence of a $θ$ Term. https://doi.org/10.1103/physrevd.55.3966

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