Does This Ontological Commitment Make Me Look Fat? A Defense of Many-Worlds

大介 加地

Cristian Alberto Orozco

Slavoj Žižek has famously suggested that quantum mechanics reveals a fundamentally unfinished reality: a world that hesitates, fails to fully actualize itself, and only becomes determinate through acts of observation. This idea is often framed through the metaphor of a “lazy God” who economizes on ontology, much like a video game that renders the world only when the player approaches it. In this essay, I argue that this metaphor is deeply misleading. By replacing the video game with a different and less glamorous model—the Sudoku puzzle—I propose an alternative ontological reading of quantum indeterminacy. On this view, indeterminacy is not ontological but epistemic, not a feature of reality itself but of our perspectival access to a globally fixed structure. The essay connects this claim to a higher-dimensional ontological framework and to a model of post-realization modal collapse, according to which the world is fully determined once it occurs, even if it remains locally opaque. The result is a direct challenge to the “lazy God” thesis and a defense of a radically non-creative, non-dynamic ontology.

Giuseppe Vitiello

Ian Staley

Deutsch's influential argument holds that the exponential speedup of quantum algorithms such as Shor's is best explained by computation distributed across ontologically real parallel branches of the wavefunction. This paper interrogates that claim by asking what minimal ontological commitments are actually required to underwrite observed quantum computational advantages. Drawing on the framework of final-state constraints and informational pruning developed in prior work, we argue that Deutsch's computational argument depends on an unpruned Everettian ontology in which all branches persist as computational substrates. We show that pruned-histories interpretations—in which boundary conditions or decoherence-based selection mechanisms restrict the space of ontologically realized branches—can preserve the empirical predictions of quantum computation while denying the parallel-universes inference. The argument requires three positive commitments: a records-based criterion for ontological commitment, a thermodynamically graded boundary between unitary computation and outcome-stabilization, and a positive account of computational speedup grounded in global Hilbert-space structure and entanglement rather than in a population of parallel worlds. We situate this result within the ontological models framework and recent observer-dependence theorems—including Frauchiger-Renner, Bong et al., and Walleghem et al.—and engage directly with Hewitt-Horsman's functionalist defense of computational branch realism. We conclude that the Deutsch argument, while rhetorically powerful, is interpretation-laden rather than interpretation-neutral.

Ian Staley

Deutsch's influential argument holds that the exponential speedup of quantum algorithms such as Shor's is best explained by computation distributed across ontologically real parallel branches of the wavefunction. This paper interrogates that claim by asking what minimal ontological commitments are actually required to underwrite observed quantum computational advantages. Drawing on the framework of final-state constraints and informational pruning developed in prior work, we argue that Deutsch's computational argument depends on an unpruned Everettian ontology in which all branches persist as computational substrates. We show that pruned-histories interpretations—in which boundary conditions or decoherence-based selection mechanisms restrict the space of ontologically realized branches—can preserve the empirical predictions of quantum computation while denying the parallel-universes inference. The argument requires three positive commitments: a records-based criterion for ontological commitment, a thermodynamically graded boundary between unitary computation and outcome-stabilization, and a positive account of computational speedup grounded in global Hilbert-space structure and entanglement rather than in a population of parallel worlds. We situate this result within the ontological models framework and recent observer-dependence theorems—including Frauchiger-Renner, Bong et al., and Walleghem et al.—and engage directly with Hewitt-Horsman's functionalist defense of computational branch realism. We conclude that the Deutsch argument, while rhetorically powerful, is interpretation-laden rather than interpretation-neutral.

David Baker