Unitarity of Time-Like Noncommutative Gauge Theories: The Violation of Ward Identities in Time-Ordered Perturbation Theory

Thorsten Ohl; Reinhold Rückl; Jörg Zeiner

doi:10.1016/j.nuclphysb.2003.10.022

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arXiv · hep-th/0309021

Unitarity of Time-Like Noncommutative Gauge Theories: The Violation of Ward Identities in Time-Ordered Perturbation Theory

Thorsten Ohl·Reinhold Rückl·Jörg Zeiner

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Abstract

We study Ward identities for simple processes with external gauge bosons in the time-ordered perturbation theory approach to time-like noncommutative gauge theories. We demonstrate that these Ward identities cannot be satisfied when all orders in the noncommutativity parameters theta_i0 are taken into account. We conclude that in time-ordered perturbation theory one cannot solve the unitarity problem of time-like noncommutative quantum field theories.

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Thorsten Ohl, Reinhold Rückl, Jörg Zeiner. 2003-10-17. Unitarity of Time-Like Noncommutative Gauge Theories: The Violation of Ward Identities in Time-Ordered Perturbation Theory. https://doi.org/10.1016/j.nuclphysb.2003.10.022

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