Quantum Entanglement in Time
  The temporal Bell inequalities are derived from the assumptions of realism and locality in time. It is shown that quantum mechanics violates these inequalities and thus is in conflict with the two assumptions. This can be used for performing certain tasks that are not possible classically. Our results open up a possibility for introducing the notion of entanglement in time in quantum physics. 
Caslav Brukner, Samuel Taylor, Sancho Cheung and Vlatko Vedral