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arXiv · hep-th/0203165

Nonplanar Anomalies in Noncommutative Theories and the Green-Schwarz Mechanism

Adi Armoni·Esperanza Lopez·Stefan Theisen
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Abstract

We discuss nonplanar anomalies in noncommutative gauge theories. In particular we show that a nonplanar anomaly exists when the external noncommutative momentum is zero and that it leads to a non-conservation of the associated axial charge. In the case of nonplanar local anomalies, a cancellation of the anomaly can be achieved by a Green-Schwarz mechanism. In an example of D3 branes placed on orbifold singularity that leads to a chiral theory, the mechanism involves twisted RR fields which propagate with zero noncommutative momentum. Global anomalies are not cancelled and, in particular, the decay pi0 --> 2 gamma is allowed.

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Adi Armoni, Esperanza Lopez, Stefan Theisen. 2002-07-02. Nonplanar Anomalies in Noncommutative Theories and the Green-Schwarz Mechanism. https://doi.org/10.1088/1126-6708%2F2002%2F06%2F050

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