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arxiv: 2605.12546 · v1 · pith:R3NQYPQOnew · submitted 2026-05-09 · 🪐 quant-ph · hep-ph

Quantum Field-Theoretic Predictions of {Psi}-Epistemic Models of Quantum Mechanics

\.Inan\c{c} \c{S}ahin This is my paper

Pith reviewed 2026-05-14 21:13 UTC · model grok-4.3

classification 🪐 quant-ph hep-ph
keywords ψ-epistemic modelsquantum field theoryLorentz symmetryscattering cross sectionsdecay widthsontological modelsquantum foundations
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The pith

ψ-epistemic models that preserve Lorentz symmetry produce deviations from standard quantum field theory in polarized scattering cross sections and decay widths.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper establishes that ψ-epistemic models, which treat the quantum state as an observer's knowledge rather than physical reality, will generate measurable differences from ordinary quantum mechanics when Lorentz symmetry is imposed. These differences appear directly in high-energy processes through altered polarized scattering cross sections and modified decay widths. The argument relies only on symmetry preservation and does not require constructing a full relativistic version of the ontological models or invoking the Harrigan-Spekkens criterion. A reader would care because this moves tests of the wave function's ontological status out of non-relativistic quantum-information laboratories and into the domain of particle-physics observables that are already measured.

Core claim

Assuming that ψ-epistemic models respect Lorentz symmetry, we show that they can give rise to deviations from standard quantum field-theoretic predictions through modifications of polarized scattering cross sections and decay widths. Our results do not require a relativistic formulation of ontological models or of the Harrigan-Spekkens criterion; Lorentz symmetry alone is sufficient. The present work constitutes a proof-of-principle study demonstrating that particle physics tests of the ontological status of the quantum state are possible and that ψ-epistemic models may exhibit experimentally distinguishable signatures in particle phenomenology.

What carries the argument

Lorentz symmetry preservation in ψ-epistemic models, which modifies the amplitudes that determine polarized scattering cross sections and decay widths.

Load-bearing premise

That ψ-epistemic models respect Lorentz symmetry and that this symmetry by itself produces observable deviations in quantum field theory without needing a complete relativistic formulation of the models.

What would settle it

A precision measurement of a polarized scattering cross section or decay width that agrees with standard quantum field theory predictions to the precision where the model predicts a detectable deviation would falsify the claim.

Figures

Figures reproduced from arXiv: 2605.12546 by \.Inan\c{c} \c{S}ahin.

Figure 1
Figure 1. Figure 1: Angular distribution of the polarized differential [PITH_FULL_IMAGE:figures/full_fig_p022_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: Surface plots of the differential cross section for t [PITH_FULL_IMAGE:figures/full_fig_p023_2.png] view at source ↗
read the original abstract

$\Psi$-epistemic models of quantum mechanics imply that the quantum state does not correspond to physical reality, but instead reflects the observer's knowledge of the underlying quantum system. The epistemic view of the quantum state has the potential to shed light on several foundational problems of quantum theory and has attracted considerable attention in the literature. On the other hand, the Pusey-Barrett-Rudolph theorem demonstrated that broad classes of $\psi$-epistemic models must lead to predictions that deviate from those of quantum mechanics. Although the original theorem involved entangled joint measurements on composite systems, alternative no-go theorems involving measurements on single quantum systems were developed shortly thereafter. Experimental investigations of the deviations predicted by $\psi$-epistemic models from quantum mechanics are still ongoing. So far, such tests have been performed within the framework of non-relativistic quantum mechanics and predominantly rely on quantum information based measurement procedures. In this work, assuming that $\psi$-epistemic models respect Lorentz symmetry, we show that they can give rise to deviations from standard quantum field-theoretic predictions through modifications of polarized scattering cross sections and decay widths. Our results do not require a relativistic formulation of ontological models or of the Harrigan-Spekkens criterion; Lorentz symmetry alone is sufficient. The present work constitutes a proof-of-principle study demonstrating that particle physics tests of the ontological status of the quantum state are possible and that $\psi$-epistemic models may exhibit experimentally distinguishable signatures in particle phenomenology.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 2 minor

Summary. The paper claims that ψ-epistemic models of quantum mechanics, under the assumption that they respect Lorentz symmetry, can produce observable deviations from standard quantum field theory predictions specifically through modifications to polarized scattering cross sections and decay widths. It presents this as a proof-of-principle that particle-physics observables could test the ontological status of the quantum state, without requiring a full relativistic formulation of ontological models or the Harrigan-Spekkens criterion; Lorentz symmetry alone is asserted to suffice.

Significance. If the central derivations hold and yield concrete, falsifiable modifications, the result would be significant for bridging quantum foundations with high-energy phenomenology, offering a new experimental avenue beyond non-relativistic quantum-information tests. The work correctly identifies that existing no-go theorems have not yet been explored in the relativistic domain and that symmetry constraints could in principle constrain epistemic models, which is a worthwhile direction if the modifications can be made explicit and parameter-free.

major comments (2)
  1. [Abstract] Abstract and introduction: the assertion that 'Lorentz symmetry alone is sufficient' to derive specific deviations in polarized cross sections and decay widths is load-bearing for the central claim but is not supported by an explicit derivation or formula showing how the epistemic character of ψ alters matrix elements or polarization sums. Lorentz invariance constrains tensor structures but does not uniquely fix the form of the modification without additional ansätze, as noted in the stress-test.
  2. [Main text] Main derivation section (presumed §3 or equivalent): without an explicit relativistic application of the Harrigan-Spekkens criterion to field operators or a concrete ontological model, the claimed modifications to cross sections remain underdetermined. The paper must supply at least one worked example (e.g., a specific polarized process with the modified |M|^2) to demonstrate that the deviation follows from symmetry rather than from an extra assumption.
minor comments (2)
  1. [Abstract] Abstract: the phrase 'modifications of polarized scattering cross sections and decay widths' is too vague; a single illustrative formula or order-of-magnitude estimate would help readers assess experimental accessibility.
  2. [References] References: the manuscript should cite recent experimental bounds on ψ-epistemic models (e.g., from single-system tests) to clarify how the proposed QFT signatures differ in scale or signature from existing limits.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for their careful and constructive review of our manuscript. The comments have prompted us to strengthen the explicitness of our derivations and examples. We address each major point below and have revised the manuscript accordingly.

read point-by-point responses

  1. Referee: [Abstract] Abstract and introduction: the assertion that 'Lorentz symmetry alone is sufficient' to derive specific deviations in polarized cross sections and decay widths is load-bearing for the central claim but is not supported by an explicit derivation or formula showing how the epistemic character of ψ alters matrix elements or polarization sums. Lorentz invariance constrains tensor structures but does not uniquely fix the form of the modification without additional ansätze, as noted in the stress-test.

    Authors: We appreciate the referee's identification of this load-bearing claim. The manuscript's reasoning is that Lorentz symmetry applied to the ontic states of a ψ-epistemic model constrains the admissible epistemic distributions such that any resulting deviation in observables must preserve the symmetry; this restricts the possible modifications to polarized matrix elements and polarization sums without requiring a full relativistic ontological model. However, we agree that the presentation would benefit from greater explicitness. In the revised version we have added a dedicated paragraph in the introduction together with a short derivation showing how the Lorentz-invariant epistemic measure alters the effective polarization projector, yielding a concrete (though model-dependent) correction to the standard QFT result. revision: yes

  2. Referee: [Main text] Main derivation section (presumed §3 or equivalent): without an explicit relativistic application of the Harrigan-Spekkens criterion to field operators or a concrete ontological model, the claimed modifications to cross sections remain underdetermined. The paper must supply at least one worked example (e.g., a specific polarized process with the modified |M|^2) to demonstrate that the deviation follows from symmetry rather than from an extra assumption.

    Authors: We agree that a concrete worked example is necessary to demonstrate that the deviation is a direct consequence of the Lorentz-symmetry assumption. The original manuscript presented the general argument but did not include a fully worked process. In the revision we have inserted a new subsection that treats polarized e⁺e⁻ → μ⁺μ⁻ annihilation. Starting from a Lorentz-covariant epistemic distribution over ontic field configurations, we derive the modified |M|², show the resulting correction to the differential cross section, and verify that the correction vanishes in the unpolarized case while remaining nonzero for specific polarization choices—thereby illustrating that the effect follows from symmetry alone. revision: yes

Circularity Check

0 steps flagged

No significant circularity; derivation relies on external symmetry assumption without reduction to inputs

full rationale

The paper assumes ψ-epistemic models respect Lorentz symmetry and claims this suffices to derive possible modifications to polarized scattering cross sections and decay widths, without requiring a full relativistic ontological model. No equations or steps in the abstract reduce a prediction to a fitted parameter, self-definition, or load-bearing self-citation. The PBR theorem and Harrigan-Spekkens criterion are cited as external results, not derived internally. The argument is presented as a proof-of-principle based on symmetry constraints alone, leaving the specific form of deviations underdetermined but not circular by construction. This matches the reader's assessment that no fitting to the same data occurs.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

Abstract-only review provides no explicit list of free parameters, axioms, or invented entities; the central claim rests on the unstated assumption that Lorentz symmetry can be imposed on ψ-epistemic models without further structure.

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Reference graph

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