Noncommutative field theory and Lorentz violation - art. no. 141601

The role of Lorentz symmetry in noncommutative field theory is considered. Any realistic noncommutative theory is found to be physically equivalent to a subset of a general Lorentz-violating standard-model extension involving ordinary fields. Some theoretical consequences are discussed. Existing exp eriments bound the scale of the noncommutativity parameter to (10 TeV)(-2).