Low-energy constraints on κ-Minkowski extension of the Standard Model

We investigate the phenomenological consequences of kappa-Minkowski extension of the Standard Model, working in the linear order in inverse kappa. At this order the *-deformed Lagrangian can be expanded in the series of dimension five operators that have non-trivial transformation properties tinder the ordinary Lorentz invariance. Such operators cause the Lorentz-violating signatures at low energies, and in particular lead to the anomalous spin precession linked to the external direction. The experimental bounds on this phenomenon then restrict parameter kappa to be above 10(23) GeV, making it difficult to impose a direct connection between this theory and quantum gravity. (C) 2009 Elsevier B.V. All rights reserved.