We present a new definition of computationally binding commitment
schemes in the quantum setting, which we call "collapse-binding". The
definition applies to string commitments, composes in parallel, and
works well with rewinding-based proofs. We give simple constructions
of collapse-binding commitments in the random oracle model, giving
evidence that they can be realized from hash functions like SHA-3. We
evidence the usefulness of our definition by constructing three-round
statistical zero-knowledge quantum arguments of knowledge for all NP
languages.
↧