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arXiv · 2505.18508

Performance report of heuristic algorithm that cracked the largest Gset Ising problems (G81 cut=14060)

Kenneth M. Zick
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Abstract

For the past 25 years, the Gset benchmark problems have challenged all manner of Ising and Max-Cut solvers. The largest of these problems have remained unsolved by any heuristic algorithm. In this report we provide data showing dramatically better speed and accuracy on these large sparse problems. Our newly discovered heuristic algorithm called Cosm reaches high (99.9% of best) solution quality orders of magnitude faster than the previous best heuristic solver results. Additionally, when afforded enough steps Cosm attains higher cuts than ever previously reported, specifically on instances G72 (cut=7008), G77 (cut=9940), and the 20,000-variable G81 (cut=14060). This report includes solution bitstrings so that the cuts can be independently validated. Remarkably, the new best solutions appear to be optimal. We believe the results are an early hint of disruptive opportunities for unconventional, hardware-centric approaches to algorithm discovery.

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Kenneth M. Zick. 2025-05-24. Performance report of heuristic algorithm that cracked the largest Gset Ising problems (G81 cut=14060). https://arxiv.org/abs/2505.18508

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