collaborators

8 papers

quant-ph2026

Making Existing Quantum Position Verification Protocols Secure Against Arbitrary Transmission Loss

Rene Allerstorfer, Andreas Bluhm, Harry Buhrman +4

Signal loss poses a significant threat to the security of quantum cryptography when the chosen protocol lacks loss-tolerance. In quantum position verification (QPV) protocols, even…

quant-ph2025

Fine-Grained Complexity via Quantum Natural Proofs

Yanlin Chen, Yilei Chen, Rajendra Kumar +2

Buhrman, Patro, and Speelman presented a framework of conjectures that together form a quantum analogue of the strong exponential-time hypothesis and its variants. They called it t…

quant-ph2025

QSETH strikes again: finer quantum lower bounds for lattice problem, strong simulation, hitting set problem, and more

Yanlin Chen, Yilei Chen, Rajendra Kumar +2

While seemingly undesirable, it is not a surprising fact that there are certain problems for which quantum computers offer no computational advantage over their respective classica…

quant-ph2025

Single-qubit loss-tolerant quantum position verification protocol secure against entangled attackers

Llorenç Escolà -Farrà s, Florian Speelman

Protocols for quantum position verification (QPV) which combine classical and quantum information are insecure in the presence of loss. We study the exact loss-tolerance of the mos…

quant-ph2025

Quantum Catalytic Space

Harry Buhrman, Marten Folkertsma, Ian Mertz +4

Space complexity is a key field of study in theoretical computer science. In the quantum setting there are clear motivations to understand the power of space-restricted computation…

quant-ph2025

Lossy-and-Constrained Extended Non-Local Games with Applications to Quantum Cryptography

Llorenç Escolà -Farrà s, Florian Speelman

Extended non-local games are a generalization of monogamy-of-entanglement games, played by two quantum parties and a quantum referee that performs a measurement on their local quan…