Quantum Computing on Lattices using Global Two-Qubit Gate
  We study the computation power of lattices composed of two dimensional systems (qubits) on which translationally invariant global two-qubit gates can be performed. We show that if a specific set of 6 global two qubit gates can be performed, and if the initial state of the lattice can be suitably chosen, then a quantum computer can be efficiently simulated 
G. Ivanyos, S. Massar, A. B. Nagy