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It is unknown whether this continues to the much larger codes that useful computations need, or whether rare correlated events set a floor.","posed_since":"","precise":"For surface-code memories on superconducting hardware, the logical error per cycle is modeled as $\\epsilon_L(d) \\sim A \\Lambda^{-(d+1)/2}$ with code distance $d$; Google Quantum AI (Nature 638, 920, 2025, arXiv:2408.13687) reported $\\Lambda$ of about 2.1 up to $d = 7$. Determine whether this law holds to $d \\ge 15 \\text{ and } \\epsilon_L \\le 10^{-10}$ per cycle, or whether correlated, leakage or drift events produce a floor; the answer is the measured $\\epsilon_L(d)$ curve or a validated model of its floor.","problem_ref":"4b0b1c6e24820c4ae743cb2eb142f30d701b7bbbb0fff87f2bee05b72376ab2f","references":"","settled_by":"Surface-code memory experiments at $d \\ge 15$ with logical error rates measured down to $10^{-10}$ per cycle, or an identified error mechanism that provably caps suppression.","status_note":"In the same 2025 work, repetition codes up to $d = 29$ reached a logical-error floor near $10^{-10}\\ \\text{per cycle}$ (approximate), set by rare correlated events occurring about once per hour.","title":"Does logical error suppression continue exponentially to large code 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