| In this paper we study the particle models in the Lorentz space L4 on the non-nullcurves.We consider the functional:∫rf(k1,k2)ds is a smooth real function ofk1 and k2.In order to solve the corresponding Euler-Lagrange equations,three Killing vectorfields:P1,P2,P3,where P1,P2 are translational vector fields and P3 is rotational one,we willobtain three constants c,which are also first integral constants of Euler-Lagrange equation.Then we decrease the degrees of freedom of the Euler-Lagrange equation.We also used therelations among P1,P2,P3 to solve the motion equations.If we set the planeΠto be spannedby P1 and P2.Furthermore in two cases:Πis degenerate andΠis non-degenerate,we givethe corresponding represents of the motion equations by cylindrical coordinates.We expressthe first curvature k1 of the critical curves by using Jacobi elliptical functions for the elasticfunctional∫rk12ds.For the elastic functional∫rak1+bk2ds,where a,b are any constants inR,we give the relation of the curvatures:k1,k2,k3 of the respective critical curves. |