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Perturbative Instabilities on the Non-Commutative Torus, Morita Duality and Twisted Boundary Conditions

Z. Guralnik·R. C. Helling·K. Landsteiner·E. Lopez
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Abstract

We study one-loop corrections in scalar and gauge field theories on the non-commutative torus. For rational theta, Morita equivalence allows these theories to be reformulated in terms of ordinary theories on a commutative torus with twisted boundary conditions. UV/IR mixing does not lead to singularities, however there can be large corrections. In particular, gauge theories show tachyonic instabilities for some of the modes. We discuss their relevance to spontaneous Z_N x Z_N symmetry breaking in the Morita dual SU(N) theory due to electric flux condensation.

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Z. Guralnik, R. C. Helling, K. Landsteiner, E. Lopez. 2002-04-03. Perturbative Instabilities on the Non-Commutative Torus, Morita Duality and Twisted Boundary Conditions. https://doi.org/10.1088/1126-6708%2F2002%2F05%2F025

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