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A Note on Unitarity of Non-Relativistic Non-Commutative Theories

Toni Mateos·Alex Moreno
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Abstract

We analyze the unitarity of a non-relativistic non-commutative scalar field theory. We show that electric backgrounds spoil unitarity while magnetic ones do not. Furthermore, unlike its relativistic counterparts, unitarity can not be restored (at least at the level of one-to-one scattering amplitude) by adding new states to the theory. This is a signal that the model cannot be embedded in a natural way in string theory.

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Toni Mateos, Alex Moreno. 2001-05-02. A Note on Unitarity of Non-Relativistic Non-Commutative Theories. https://doi.org/10.1103/physrevd.64.047703

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