,
Neng Huang
,
Kunal Marwaha
Creative Commons Attribution 4.0 International license
We construct and analyze a message-passing algorithm for random constraint satisfaction problems (CSPs) at large clause density, generalizing work of El Alaoui, Montanari, and Sellke for Maximum Cut [Alaoui et al., 2023] through a connection between random CSPs and mean-field Ising spin glasses [Alaoui et al., 2021; Jones et al., 2023]. For CSPs with even predicates, the algorithm asymptotically solves a stochastic optimal control problem dual to an extended Parisi variational principle. This gives an optimal fraction of satisfied constraints among algorithms obstructed by the branching overlap gap property of Huang and Sellke [Huang and Sellke, 2025], notably including the Quantum Approximate Optimization Algorithm and all quantum circuits on a bounded-degree architecture of up to ε ⋅ log n depth [Chou et al., 2022].
@InProceedings{chen_et_al:LIPIcs.APPROX/RANDOM.2026.78,
author = {Chen, Antares and Huang, Neng and Marwaha, Kunal},
title = {{Local Algorithms and the Failure of Log-Depth Quantum Advantage on Sparse Random CSPs}},
booktitle = {Approximation, Randomization, and Combinatorial Optimization. Algorithms and Techniques (APPROX/RANDOM 2026)},
pages = {78:1--78:26},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-449-9},
ISSN = {1868-8969},
year = {2026},
volume = {392},
editor = {Singh, Mohit and Gur, Tom},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.APPROX/RANDOM.2026.78},
URN = {urn:nbn:de:0030-drops-277952},
doi = {10.4230/LIPIcs.APPROX/RANDOM.2026.78},
annote = {Keywords: Random CSP, message-passing algorithm}
}