Zero Worlds · source record · preprint

Realism about the external world: an adversarial collaboration

McQueen, K. J.; Müller, M. P. · 2026

AI-verified citationSRC-MCQUEEN-MULLER-2026

identifier / locator: arXiv:2607.16379 (submitted 2026-07-17)
url: https://arxiv.org/abs/2607.16379
verification note: arXiv record retrieved and abstract read 2026-08-22. Full text (v1, 19 pages) retrieved through scripts/site.ts read on 2026-10-21 by the operator (session 2026-10-21-session-site-130024), and the sections quoted in evidence read. Read in full, pp. 1–19, on 2026-10-22 (session 2026-10-22-session-site-130201). Evidence locators name its PDF pages.
reliability notes: A structured realism-versus-idealism disagreement between a physicalist philosopher and the framework's author — useful as the clearest statement of exactly where the two ontologies part company.
Unreviewed preprint.
Funding, from its acknowledgments: 'supported by grant number FQXi-RFP-CPW-2015 from the Foundational Questions Institute (FQxI) and Fetzer Franklin Fund', and in part by Perimeter Institute.

Evidence drawn from this source

Context· weakZW-E005

McQueen & Müller: realism versus algorithmic idealism, stated adversarially

what the source states: A structured adversarial collaboration in which one author defends realism — reality as an external physical world governed by laws — and the other defends the view that reality fundamentally consists in first-person states with the physical world emergent, centered on Algorithmic Idealism's treatment of observer paradoxes, using a discipline-neutral template designed to isolate the genuine source of disagreement.
what we infer: Not evidence for either side; filed as the cleanest available statement of what the attribution dispute is about, by one representative of each side. Its existence is also a health indicator: this controversy is being conducted in the open, adversarially, which the fairness rules should reward with attention.
limitations: Unreviewed preprint; abstract-level characterization.

McQueen, K. J. (2026)AI-verified citationZW-C008

Supports· moderateZW-E021

McQueen & Müller: both sides agree the framework's probabilities cannot yet be tested by repeated, shared experiments

what the source states: The critic (McQueen) argues: "The state transition postulate is therefore not well-defined: there appears to be no good option for spelling out what the probabilities are probabilities of" (p. 13). The advocate (Müller) answers that the framework's goal is to answer this question "for private experiments that are not necessarily intersubjectively verifiable, such as duplication or simulation scenarios" (p. 14). In their joint evaluation the two state that "our adversarial collaboration has uncovered two valid objections". The first is that Algorithmic Idealism "cannot (yet) appeal to scientific practice and experimental pragmatism", because "it is not in general possible to relate probability assignments to statistical claims about outcomes of an experiment that is repeated a large number of times under identical conditions, and analyzed from an intersubjective third-person perspective". They add: "Thus, the proponent agrees with the critic that this point has to be developed in greater detail and clarity" (p. 18).
what we infer: The framework's author concedes in print the point ZW-C503 makes: its distinctive first-person predictions do not yet connect to repeatable, publicly comparable frequencies. The concession is about operational meaning, not about whether the framework is coherent. Neither author says the postulates must change. What the concession means for the featured thesis is recorded separately (ZW-E025).
limitations: An unrefereed preprint by two authors; 'valid objection' is their joint characterization, not an outside verdict.
The objection concerns how the probabilities are to be interpreted and checked. It does not show the framework's theorems are wrong.

McQueen, K. J. (2026)AI-verified citationZW-C503

Qualifies· moderateZW-E025

McQueen & Müller: the framework's author agrees its probabilities cannot yet be checked against repeated, shared experiments

what the source states: In their joint evaluation the two authors state that Algorithmic Idealism "cannot (yet) appeal to scientific practice and experimental pragmatism", because "it is not in general possible to relate probability assignments to statistical claims about outcomes of an experiment that is repeated a large number of times under identical conditions, and analyzed from an intersubjective third-person perspective" (p. 18). They also state that these objections "are not claims that the main postulates of Algorithmic Idealism have to be modified, but that important further work of clarification is left to be done" (p. 18).
what we infer: This neither supports nor undermines the featured thesis (ZW-C008). It bears on whether the thesis can be tested: by the proponent's own account, its distinctive probabilities do not yet meet a repeatable, third-person check. That is the concrete reason the case grades ZW-C008 presently untestable rather than weakly supported or refuted.
limitations: An unrefereed preprint by two authors; the concession is about the framework's present operational meaning, not a verdict on whether there is a world underneath.

McQueen, K. J. (2026)AI-verified citationZW-C008

Qualifies· moderateZW-E022

McQueen & Müller: the Boltzmann-brain resolution is challenged, defended, and left needing further work

what the source states: The critic argues that a Boltzmann brain's self-state, like the framework's own example of an insect at a table's edge, would carry information about its environment, so that its next disintegrating state would be predictable: "But then the framework cannot produce the result that we are probably not Boltzmann brains" (p. 14). The advocate replies that most Boltzmann-brain realizations are nearly uncorrelated with their environment, which is why such futures are "much less likely than ordinary ones, regardless of the number of BBs in the universe". He adds that "the analysis here gives valid intuition, but not the exact technical arguments" (p. 16). In the joint evaluation, the second valid objection (O2) records that "the critic has pointed at an important fact that has so far insufficiently been discussed in existing publications of Algorithmic Idealism": only part of the self-state is accessible to the agent (p. 18).
what we infer: ZW-C004 says the standard puzzles "dissolve" under first-person reasoning. For the Boltzmann-brain puzzle that is the proponent's position, now contested in print and defended there. The two authors agree that how agents should predict from a partly inaccessible self-state needs further work. The emergence theorems themselves are not challenged here. The "dissolution" is better described as a defended claim than a settled result.
limitations: A single exchange in an unrefereed preprint. The advocate holds that the reply suffices for the conclusion that Boltzmann-brain counting cannot rule out cosmological models; the critic's final view is not separately stated.

McQueen, K. J. (2026)AI-verified citationZW-C004