SEQReT – Symmetry-Enhanced Quantum Cryptography with Representation Theory

The need to secure information permeates all layers of today’s digitalized society, individuals, companies, and governmental institutions. Goals are, e.g., communication privacy, secure transactions, and countering censorship and disinformation.

Quantum cryptography (QC) offers highly secure solutions, for, e.g., randomness generation and secret key exchange. Quantum correlations enable security under minimal assumptions, even with untrusted devices (device independent (DI) QC). Such ultra-high assurance comes at a cost: DI-QC is technologically challenging and inefficient. Semi-device-independent quantum cryptography (SDI-QC) strikes a balance between minimal trust and efficiency.

We will take on two bottlenecks of SDI-QC, a feasibility barrier and an efficiency bottleneck.  We aim to overcome both barriers using representation theory. Especially in the multi-party setting, we will exploit symmetries to reduce complexity and thus enable feasible and efficient analysis.