Challenge

No finite set of state properties orders classical simulation cost

Published · Publication and review standards

Effect on the theory

Corrects an error

Effect score 68/100Major

Major. Forces a change to a foundation section or corrects an error. Major: it corrects the programme's own earlier design and is now one of the three settled results in foundation section 1. The constructive half is verified in code rather than argued. It stays below the very major band because it concerns the instrument, not any host.

Progress to an answer: 2 of 100 — a small step. A small step. It removes a false assumption that was blocking the branch, but it narrows no space of hosts and is a result about the programme's own tools. See the running chart.

AI-assisted score · · How scores work

Corrects the programme's own earlier quantum test design. The proxy regression needed classical simulation cost to be ordered by a fixed set of state properties. Session 005 shows it is not: at n = 12, a state that is an exact product state in a known Clifford frame matches another state to within 0.0008 in magic and 0.0014 in entanglement. The constructive half is verified in code and rests on no preprint. The result concerns the instrument and is not evidence about whether reality is simulated.

Next step
Keep the matched-twin design that replaced the regression, and do not reintroduce a fixed cost proxy in later protocols.

AI-assisted editorial assessment · · This assessment can be challenged; it is separate from the contributor’s claim.

The contribution

Explain simply

An earlier version of the quantum test assumed that simulation cost could be predicted from a few measurable properties of a quantum state, such as its entanglement and its magic. A simulation study found two 12-qubit states that match on both properties yet differ sharply in how hard they are to simulate. One of them is secretly simple. The original test design therefore had no valid target and was replaced. This is a result about the programme's own instrument, found in simulation, and it is not evidence about whether reality is simulated.

Summary supplied by the contributor; it shares the review status of the full submission.

Drafted by the AI system Anthropic Claude (Claude Opus 5) for the owner-seeded Reality Compute research programme, from the Session 005 code bundle and its captured output, produced in AI-assisted research sessions with the owner. Human verification: independent human verification has not been recorded. This reports a simulation result about the programme's own test design. It is not a hardware experiment and not evidence that reality is simulated. The claim is narrow. Classical simulation cost is not a function of any fixed finite set of state properties. In particular, magic (the stabilizer Rényi entropy M₂) and entanglement (the Rényi-2 entropy S₂) together do not order cost. The programme's first quantum test, a regression of output error on a complexity proxy, needed exactly that ordering. Without it the regression has no valid target. The decisive case is at n = 12 qubits. State X is a Clifford circuit applied to a product of twelve single-qubit magic states. State Y is a Clifford+T circuit with its T gates spread over four magic layers, tuned so that the two states differ by only 0.0008 in M₂ and 0.0014 in S₂. In the computational basis both have bond dimension χ = 64, the maximum possible at this width. The magic measure used here follows Leone, Oliviero and Hamma, Stabilizer Rényi entropy. The two states are not equally hard. X is an exact product state in the Clifford frame its own construction supplies, with χ = 1. The verification suite checks this directly, and it also confirms that every single-qubit marginal of the transformed state is pure. For Y, the best of 200 random Clifford frames reached χ = 32. A simulator that knows X's frame pays almost nothing, while the two-coordinate metric predicts maximal cost for both. A wider scan points the same way. At n = 10, 174 sampled states produced 186 pairs matched to within 0.05 in both S₂ and M₂, and bond dimension differed by up to 2.00× inside a matched cell. All 9 verification checks passed. They include brute-force enumeration of all 4ⁿ Pauli strings at n = 3 and 4, and bit-for-bit reproduction of X from the seed. My analysis, which is proposed rather than established: the failure is structural, not a matter of picking better coordinates. Clifford circuits leave M₂ unchanged while they can create or remove almost any amount of computational-basis entanglement. So a state's cost depends on whether a cheap frame exists and can be found, and neither fact is recorded by a finite list of basis-independent properties. The strongest competing interpretation is that Y also has a cheap frame that 200 random draws missed, so the pair shows a search failure rather than a cost difference. That is possible, and the captured output says so. But the argument does not rest on Y. X alone is cheap at coordinates where the metric predicts maximal cost, and that single construction is enough to show cost is not a function of those two coordinates. The result has two limits. It does not show that cost can never be bounded by some properties, only that a fixed finite set does not determine it. And it shows that holding the right coordinates is not enough: X's own cheap frame was not found by the same 200 random draws, so knowing that a cheap frame exists does not make it computable. The practicable consequence has already been taken. Session 006 replaced the proxy regression with RCC-A2, a matched-twin comparison that certifies a cost difference inside each pair instead of ranking all circuits by a proxy. The constructive half of this argument is verified in the code bundle and does not depend on any preprint. Requested theory update: record in the Consolidated Master v1.6, §3.1, that the Session 005 result corrects the programme's own earlier design, with its figures and both limits, as set out in the v1.6 master. No architecture's status changes.

Test, uncertainty or challenge

Explain simply

This section describes what could support or challenge the idea, or what evidence is still missing. Check whether the proposed result would really separate different explanations.

Reading guide, not a summary of the contributor’s claim.

The claim fails if a fixed, finite set of efficiently computable state properties is shown to determine classical simulation cost up to a bounded factor across the state families used here, including Clifford-dressed product magic states. A concrete check: take state X from Session 005 (seed 20260908) and exhibit a property in the fixed set that separates it from states of equal magic and entanglement whose bond dimension stays at 32 or more in every Clifford frame. Finding a cheap Clifford frame for state Y would not refute the claim, because the argument rests on X.

Sources & supporting material

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A link helps you check where a claim came from. It does not automatically confirm the claim. Compare what the source actually says with how it is used here.

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