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arXiv · hep-th/0002177

Quantum Field Theories on Null Surfaces

Kumar S. Gupta·Badis Ydri
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Abstract

We study the behaviour of quantum field theories defined on a surface $S$ as it tends to a null surface $S_n$. In the case of a real, free scalar field theory the above limiting procedure reduces the system to one with a finite number of degrees of freedom. This system is shown to admit a one parameter family of inequivalent quantizations. A duality symmetry present in the model can be used to remove the quantum ambiguity at the self-dual point . In the case of the non-linear $σ$-model with the Wess-Zumino-Witten term a similar limiting behaviour is obtained. The quantization ambiguity in this case however cannot be removed by any means.

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Kumar S. Gupta, Badis Ydri. 2000-05-22. Quantum Field Theories on Null Surfaces. https://doi.org/10.1142/s0217751x01003421

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