Exploring Bit Commitments in Quantum Cryptography

James Bartusek (UC Berkeley)
https://simons.berkeley.edu/talks/james-bartusek-uc-berkeley-2023-06-20
Minimum Quantum Assumptions for Cryptography Workshop

Bit commitments are a central object of study in quantum cryptography. On the one hand, they are implied by assumptions potentially weaker than one-way functions, such as pseudorandom quantum states. On the other hand, they have applications beyond what is known (or possible) classically, implying protocols with better functionality (i.e. oblivious transfer) and better security (i.e. certified everlasting hiding). In this talk, we will see how to construct protocols that satisfy various flavors of certified everlasting security, from the minimal assumption of (the black-box use of) standard bit commitments. Along the way, we will review the construction of oblivious transfer from commitments, and introduce a novel security notion that we call everlasting security transfer. Based on joint work with Dakshita Khurana.