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arXiv · 0706.3244

A non-perturbative study of non-commutative U(1) gauge theory

J. Nishimura·W. Bietenholz·Y. Susaki·J. Volkholz
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Abstract

We study U(1) gauge theory on a 4d non-commutative torus, where two directions are non-commutative. Monte Carlo simulations are performed after mapping the regularized theory onto a U(N) lattice gauge theory in d=2. At intermediate coupling strength, we find a phase in which open Wilson lines acquire non-zero vacuum expectation values, which implies the spontaneous breakdown of translational invariance. In this phase, various physical quantities obey clear scaling behaviors in the continuum limit with a fixed non-commutativity parameter theta, which provides evidence for a possible continuum theory. In the weak coupling symmetric phase, the dispersion relation involves a negative IR-singular term, which is responsible for the observed phase transition.

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J. Nishimura, W. Bietenholz, Y. Susaki, J. Volkholz. 2007-06-22. A non-perturbative study of non-commutative U(1) gauge theory. https://doi.org/10.1143/ptps.171.178

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