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arXiv · hep-th/9505010

Anomalous commutators for energy-momentum tensors

Javier P. Muniain·Dardo D. Piriz
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Abstract

Anomalous contributions to the energy-momentum commutators are calculated for even dimensions, by using a non-perturbative approach that combines operator product expansion and Bjorken-Johnson-Low limit techniques. We first study the two dimensional case and give the covariant expression for the commutators. The expression in terms of light-cone coordinates is then calculated and found to be in perfect agreement with the results in the literature. The particular scenario of the light-cone frame is revisited using a reformulation of the BJL limit in such a frame. The arguments used for $n=2$ are then generalized to the case of any even dimensional Minkowskian spacetime and it is shown that there are no anomalous contributions to the commutators for $n\not=2$. These results are found to be valid for both fermionic and bosonic free fields. A generalization of the BJL-limit is later used to obtain double commutators of energy-momentum tensors and to study the Jacobi identity. The two dimensional case is studied and we find no existance of 3-cocycles in both the Abelian and non-Abelian case.

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Javier P. Muniain, Dardo D. Piriz. 1995-05-02. Anomalous commutators for energy-momentum tensors. https://arxiv.org/abs/hep-th/9505010

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