5 papers
Quantum inflation and source-transfer hierarchies are complete for tree networks
Xiangling Xu, Igor Klep, Marc-Olivier Renou
Understanding the capabilities and limits of quantum systems is central to quantum information processing. This includes determining which correlations can arise in networks of qua…
The bulk spectral gap is certifiable from above but uncomputable from below
Xiangling Xu, Matthias Schötz, Jie Wang +4
Determining spectral gaps in the thermodynamic limit is a central challenge in quantum many-body physics. When a fixed boundary condition is imposed, this problem is undecidable: n…
Quantitative quantum soundness for all multipartite compiled nonlocal games
Matilde Baroni, Igor Klep, Dominik Leichtle +4
Compiled nonlocal games transfer the power of Bell-type multi-prover tests into a single-device setting by replacing spatial separation with cryptography. Concretely, the KLVY comp…
Quantitative Quantum Soundness for Bipartite Compiled Bell Games via the Sequential NPA Hierarchy
Igor Klep, Connor Paddock, Marc-Olivier Renou +4
Compiling Bell games under cryptographic assumptions replaces the need for physical separation, allowing nonlocality to be probed with a single untrusted device. While Kalai et al.…
Quantitative Tsirelson's Theorems via Approximate Schur's Lemma and Probabilistic Stampfli's Theorems
Xiangling Xu, Marc-Olivier Renou, Igor Klep
Whether an almost-commuting pair of operators must be close to a commuting pair is a central question in operator and matrix theory. We investigate this problem for pairs of -…