Lorentz violation, two-time physics, and strings

► We study the generalization of the relativistic particle proposed by Kostelecký. ► An alternative action for this system is presented. ► There is a limit where the model has more symmetries than the relativistic particle. ► When Lorentz symmetry is restored, a relationship with two-time physics is determined. ► If Poincaré symmetry is recovered, the action of a relativistic string is obtained.