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Space-Time Noncommutative Field Theories And Unitarity

Jaume Gomis·Thomas Mehen
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Abstract

We study the perturbative unitarity of noncommutative scalar field theories. Field theories with space-time noncommutativity do not have a unitary S-matrix. Field theories with only space noncommutativity are perturbatively unitary. This can be understood from string theory, since space noncommutative field theories describe a low energy limit of string theory in a background magnetic field. On the other hand, there is no regime in which space-time noncommutative field theory is an appropriate description of string theory. Whenever space-time noncommutative field theory becomes relevant massive open string states cannot be neglected.

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Jaume Gomis, Thomas Mehen. 2000-08-01. Space-Time Noncommutative Field Theories And Unitarity. https://doi.org/10.1016/s0550-3213(00)00525-3

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