A continuous/discrete fractional Noether's theorem
  We prove a fractional Noether's theorem for fractional Lagrangian systems invariant under a symmetry group both in the continuous and discrete cases. This provides an explicit conservation law (first integral) given by a closed formula which can be algorithmically implemented. In the discrete case, the conservation law is moreover computable in a finite number of steps. 
Lo\"ic Bourdin and Jacky Cresson and Isabelle Greff
math.DS