Limits of privacy amplification against non-signalling memory attacks

Abstract

The task of privacy amplification, in which Alice holds some partially secret information with respect to an adversary Eve and wishes to distill it until it is completely secret, is known to be solvable almost optimally both in the classical and quantum world. Unfortunately, when considering an adversary who is only limited by non-signalling constraints such a statement cannot be made in general. We here prove that under the natural assumptions of time-ordered non-signalling system, which allow past subsystems to signal future subsystems (using the device's memory for example), super-polynomial privacy amplification by any hashing is impossible. This is in great relevance when considering practical device independent key distribution protocols which assume a super-quantum adversary.

12 pages, 5 figures

References in corpus (2)

• Device-independent quantum key distribution secure against collective attacks
• Unconditionally secure device-independent quantum key distribution with only two devices

Cited by in corpus (16)

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• Quantum Random Number Generators
• Fully device independent quantum key distribution
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• Device-independent Randomness Amplification and Privatization
• de Finetti reductions for correlations
• Physical Security in the Post-quantum Era: A Survey on Side-channel Analysis, Random Number Generators, and Physically Unclonable Functions
• Reductions to IID in Device-independent Quantum Information Processing
• Amplifying the randomness of weak sources correlated with devices
• Limitations on device independent key secure against non signaling adversary via the squashed non-locality
• Generalised Kochen-Specker Theorem for Finite Non-Deterministic Outcome Assignments
• A No-go theorem for device-independent security in relativistic causal theories
• Regularising data for practical randomness generation
• Quantifying the randomness of copies of noisy Popescu-Rohrlich correlations
• Hybrid no-signaling-quantum correlations
• De Finetti Theorems for Quantum Conditional Probability Distributions with Symmetry