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arXiv · hep-th/0411161

Quantized equations of motion in non-commutative theories

Paul Heslop·Klaus Sibold
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Abstract

Quantum field theories based on interactions which contain the Moyal star product suffer, in the general case when time does not commute with space, from several diseases: quantum equation of motions contain unusual terms, conserved currents can not be defined and the residual spacetime symmetry is not maintained. All these problems have the same origin: time ordering does not commute with taking the star product. Here we show that these difficulties can be circumvented by a new definition of time ordering: namely with respect to a light-cone variable. In particular the original spacetime symmetries SO(1,1) x SO(2) and translation invariance turn out to be respected. Unitarity is guaranteed as well.

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Paul Heslop, Klaus Sibold. 2005-09-09. Quantized equations of motion in non-commutative theories. https://doi.org/10.1140/epjc%2Fs2005-02241-x

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