IQC Special seminar featuring Ian Thomas George

Orthogonality Broadcasting and Quantum Position Verification

by Ian Thomas George | Centre for Quantum Technologies (CQT) at National University of Singapore (NUS)

The no-cloning theorem leads to information-theoretic security in various quantum cryptographic protocols. However, this security typically derives from the possibly weaker property that classical information encoded in certain quantum states cannot be broadcast, which we call "orthogonality broadcasting."  

In this talk, we will consider orthogonality broadcasting directly. First, we will establish separations between the power of classical and quantum communication in orthogonality broadcasting. Second, we will relate orthogonality broadcasting to a class of quantum position verification (QPV) protocols. In doing so, we will establish security of QPV protocols in the no preshared entanglement model that previous methods could not.

A key technical contribution is an uncertainty relation that uses the geometric relation of the states that undergo broadcasting rather than the non-commutative aspect of the final measurements.

Based on joint work with Rene Allerstorfer, Philip Verduyn Lunel, and Eric Chitambar (arXiv: 2311.00677).

Location

• QNC 1501