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arXiv · hep-th/0104244

Comments on the Energy-Momentum Tensor in Non-Commutative Field Theories

Mohab Abou-Zeid·Harald Dorn
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Abstract

In a non-commutative field theory, the energy-momentum tensor obtained from the Noether method needs not be symmetric; in a massless theory, it needs not be traceless either. In a non-commutative scalar field theory, the method yields a locally conserved yet non-symmetric energy-momentum tensor whose trace does not vanish for massless fields. A non-symmetric tensor also governs the response of the action to a general coordinate transformation. In non-commutative gauge theory, if translations are suitably combined with gauge transformations, the method yields a covariantly constant tensor which is symmetric but only gauge covariant. Using suitable Wilson functionals, this can be improved to yield a locally conserved and gauge invariant, albeit non-symmetric, energy-momentum tensor.

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Mohab Abou-Zeid, Harald Dorn. 2001-06-29. Comments on the Energy-Momentum Tensor in Non-Commutative Field Theories. https://doi.org/10.1016/s0370-2693(01)00780-8

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