Non-Commutativity and Unitarity Violation in Gauge Boson Scattering
نویسنده
چکیده
We examine the unitarity properties of spontaneously broken non-commutative gauge theories. We find that the symmetry breaking mechanism in the non-commutative Standard Model of Chaichian et al. leads to an unavoidable violation of tree-level unitarity in gauge boson scattering at high energies. We then study a variety of simplified spontaneously broken non-commutative theories and isolate the source of this unitarity violation. Given the group theoretic restrictions endemic to non-commutative model building, we conclude that it is difficult to build a non-commutative Standard Model under the Weyl-Moyal approach that preserves unitarity. ∗Work supported by the Department of Energy, Contract DE-AC03-76SF00515
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