Another simple unconditionally secure quantum bit commitment protocol -- beating entanglement with entanglement

Abstract

It is shown how the evidence state space in quantum bit commitment may be made to depend on the bit value 0 or 1 with split entangled pairs. As a consequence, one can obtain a protocol that is perfectly concealing, but is also $\epsilon$-binding because the bit-value dependent evidence space prevents the committing party from cheating by means of a local transformation that is independent of the part of evidence state space that has never been in his possession.

3 pages, revtex4; title has changed, other significant changes (see footnote)