Quantum Security Proofs Using Semi-classical Oracles

Quantum Security Proofs Using Semi-classical OraclesA. Ambainis, M. Hamburg, and D. Unruh (Crypto 2019).  [publisher's version | eprint]

Abstract: We present an improved version of the one-way to hiding (O2H) Theorem by Unruh, J ACM 2015. Our new O2H Theorem gives higher flexibility (arbitrary joint distributions of oracles and inputs, multiple reprogrammed points) as well as tighter bounds (removing square-root factors, taking parallelism into account). The improved O2H Theorem makes use of a new variant of quantum oracles, semi-classical oracles, where queries are partially measured. The new O2H Theorem allows us to get better security bounds in several public-key encryption schemes.