  Here we propose a general relativistic quantum framework for cryptography
that exploits the fascinating connection of quantum non-locality and special
theory of relativity with cryptography. The underlying principle of
unconditional security is causality and two-fold quantum non-local
correlations: first entanglement swapping and then teleportation over causally
independent entangled systems. We show that the proposed framework has
following remarkable and novel features in mistrustful cryptography: (i) It
helps in defining a new notion of oblivious transfer where both the data
transferred and the transfer position remains oblivious. (ii) The authenticity
and integrity of the data transferred is guaranteed by the fundamental
principles of quantum theory instead of computational complexity. (iii) It
directly leads to unconditionally secure and deterministic two-sided two-party
computation which is currently considered to be impossible. (iv) the proposed
framework turns out to be asynchronous ideal coin tossing with zero bias which
has not been achieved previously. (v) The same framework also implies
unconditionally secure bit commitment. Finally, the combination of quantum
non-locality and theory of relativity as discussed here can easily be
generalized to multiparty setting that could be used to solve other mistrustful
cryptographic tasks such as secret sharing and key agreement securely.
