Quantum nonlocality allows for ever-lasting unconditionally secure bit commitment

We present a protocol for ever-lasting unconditionally secure bit commitment based on quantum nonlocality. This protocol recovers two features missing in recent relativistic bit commitment protocols, namely, that the committer can decide if and when she wants to reveal the commitment and that the security of the commitment lasts for arbitrary long time. The protocol shows that quantum nonlocality is a key ingredient for solving another fundamental cryptographic problem.