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Remarks on Time-Space Noncommutative Field Theories

L. Alvarez-Gaume·J. L. F. Barbon·R. Zwicky
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Abstract

We propose a physical interpretation of the perturbative breakdown of unitarity in time-like noncommutative field theories in terms of production of tachyonic particles. These particles may be viewed as a remnant of a continuous spectrum of undecoupled closed-string modes. In this way, we give a unified view of the string-theoretical and the field-theoretical no-go arguments against time-like noncommutative theories. We also perform a quantitative study of various locality and causality properties of noncommutative field theories at the quantum level.

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L. Alvarez-Gaume, J. L. F. Barbon, R. Zwicky. 2001-03-09. Remarks on Time-Space Noncommutative Field Theories. https://doi.org/10.1088/1126-6708%2F2001%2F05%2F057

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