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Non-renormalizability of θ-expanded noncommutative QED

Raimar Wulkenhaar
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Abstract

Computing all divergent one-loop Green's functions of θ-expanded noncommutative quantum electrodynamics up to first order in θ, we show that this model is not renormalizable. The reason is a divergence in the electron four-point function which cannot be removed by field redefinitions. Ignoring this problem, we find however clear hints for new symmetries in massless θ-expanded noncommutative QED: Four additional divergences which would be compatible with gauge and Lorentz symmetries and which are not reachable by field redefinitions are absent.

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Raimar Wulkenhaar. 2002-04-02. Non-renormalizability of θ-expanded noncommutative QED. https://doi.org/10.1088/1126-6708%2F2002%2F03%2F024

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