Quantitative quantum soundness for all multipartite compiled nonlocal games

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Baroni, Matilde, Klep, Igor, Leichtle, Dominik, Renou, Marc-Olivier, Šupić, Ivan, Tendick, Lucas, Xu, Xiangling
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866918150786777088
author Baroni, Matilde
Klep, Igor
Leichtle, Dominik
Renou, Marc-Olivier
Šupić, Ivan
Tendick, Lucas
Xu, Xiangling
author_facet Baroni, Matilde
Klep, Igor
Leichtle, Dominik
Renou, Marc-Olivier
Šupić, Ivan
Tendick, Lucas
Xu, Xiangling
contents 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 compiler (STOC'23) maps any multi-prover game to an interactive single-prover protocol, using quantum homomorphic encryption. A crucial security property of such compilers is quantum soundness, which ensures that a dishonest quantum prover cannot exceed the original game's quantum value. For practical cryptographic implementations, this soundness must be quantitative, providing concrete bounds, rather than merely asymptotic. While quantitative quantum soundness has been established for the KLVY compiler in the bipartite case, it has only been shown asymptotically for multipartite games. This is a significant gap, as multipartite nonlocality exhibits phenomena with no bipartite analogue, and the difficulty of enforcing space-like separation makes single-device compilation especially compelling. This work closes this gap by showing the quantitative quantum soundness of the KLVY compiler for all multipartite nonlocal games. On the way, we introduce an NPA-like hierarchy for quantum instruments and prove its completeness, thereby characterizing correlations from operationally-non-signaling sequential strategies. We further develop novel geometric arguments for the decomposition of sequential strategies into their signaling and non-signaling parts, which might be of independent interest.
format Preprint
id arxiv_https___arxiv_org_abs_2509_25145
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Quantitative quantum soundness for all multipartite compiled nonlocal games
Baroni, Matilde
Klep, Igor
Leichtle, Dominik
Renou, Marc-Olivier
Šupić, Ivan
Tendick, Lucas
Xu, Xiangling
Quantum Physics
Cryptography and Security
Mathematical Physics
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 compiler (STOC'23) maps any multi-prover game to an interactive single-prover protocol, using quantum homomorphic encryption. A crucial security property of such compilers is quantum soundness, which ensures that a dishonest quantum prover cannot exceed the original game's quantum value. For practical cryptographic implementations, this soundness must be quantitative, providing concrete bounds, rather than merely asymptotic. While quantitative quantum soundness has been established for the KLVY compiler in the bipartite case, it has only been shown asymptotically for multipartite games. This is a significant gap, as multipartite nonlocality exhibits phenomena with no bipartite analogue, and the difficulty of enforcing space-like separation makes single-device compilation especially compelling. This work closes this gap by showing the quantitative quantum soundness of the KLVY compiler for all multipartite nonlocal games. On the way, we introduce an NPA-like hierarchy for quantum instruments and prove its completeness, thereby characterizing correlations from operationally-non-signaling sequential strategies. We further develop novel geometric arguments for the decomposition of sequential strategies into their signaling and non-signaling parts, which might be of independent interest.
title Quantitative quantum soundness for all multipartite compiled nonlocal games
topic Quantum Physics
Cryptography and Security
Mathematical Physics
url https://arxiv.org/abs/2509.25145