Non-locality is based on the assumption that the act of observing causes an effect instantaniously elsewhere. It occurred to me that we can't be certain that one thing(observing) is causing the other(non-local wave function collapse). Another solution might be that both events are determined by a common cause in the past? i.e the prexisteng conditions that make the non-local outcome also make sure an observation is made. Has anyone heard of any theories that have explored this?