 Guifré Vidal, then at the Institute for Quantum Information, Caltech,
has recently proposed a scheme useful for simulating a certain category of quantum systems.He asserts that ""any quantum computation with pure states can be efficiently simulated with a classical computer provided the amount of entanglement involved is sufficiently restricted"
This happens to be the case with generic Hamiltonians displaying local interactions, as for example, Hubbard-like Hamiltonians.The method exhibits a low-degree polynomial behavior in the increase of computational time with respect to the amount of entanglement present in the system.