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arXiv · hep-th/0703245

QFT with Twisted Poincaré Invariance and the Moyal Product

E. Joung·J. Mourad
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Abstract

We study the consequences of twisting the Poincare invariance in a quantum field theory. First, we construct a Fock space compatible with the twisting and the corresponding creation and annihilation operators. Then, we show that a covariant field linear in creation and annihilation operators does not exist. Relaxing the linearity condition, a covariant field can be determined. We show that it is related to the untwisted field by a unitary transformation and the resulting n-point functions coincide with the untwisted ones. We also show that invariance under the twisted symmetry can be realized using the covariant field with the usual product or by a non-covariant field with a Moyal product. The resulting S-matrix elements are shown to coincide with the untwisted ones up to a momenta dependent phase.

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E. Joung, J. Mourad. 2007-04-07. QFT with Twisted Poincaré Invariance and the Moyal Product. https://doi.org/10.1088/1126-6708%2F2007%2F05%2F098

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