A Quantum Neural Network Computes Entanglement
  An outstanding problem in quantum computing is the calculation of entanglement, for which no closed-form algorithm exists. Here we solve that problem, and demonstrate the utility of a quantum neural computer, by showing, in simulation, that such a device can be trained to calculate the entanglement of an input state, something neither an algorithmic quantum computer nor a classical neural net can do. 
E.C. Behrman, V. Chandrashekar, Z. Wang, C.K. Belur, J.E. Steck, and   S.R. Skinner