From a dynamical system of the knee to natural jet geometrical objects
  In this paper we construct some natural geometrical objects on the 1-jet space J^1(R,R^3), like a nonlinear connection, a Cartan linear connection (together with its d-torsions and d-curvatures), a jet "electromagnetic" d-field and its geometric "electromagnetic" Yang-Mills energy, starting from a given dynamical system governing the three-dimensional motion of the knee in the mathematical model introduced by Grood and Suntay. The corresponding Yang-Mills energetic surfaces of constant level (produced by this knee dynamical system) are studied. 
Mircea Neagu, Mihaela Maria Marin
math.DG math.DS