{"id":"8aee12b3-6ba2-4a57-a9d7-bd2997e4c7b2","arxiv_id":"2605.24446","paper_version":2,"verdict":"UNVERDICTED","confidence":"LOW","novelty_score":7.0,"correctness_risk":"medium","formal_verification":"none","parameter_count":0,"one_line_summary":"COM exhibits KS contextuality without requiring Bohmian contextuality, showing the two are distinct.","lead":"The paper shows that the Contextual Ontological Model produces Kochen-Specker contextuality without Bohmian contextuality. This separation allows the two concepts to be studied independently in hidden-variable models.","discovery_kind":"extension","skeptic_critique":{"model":"grok-4.3","headline":"No significant objection identified","rationale":"Reader's weakest assumption matches the only plausible point of vulnerability, but the paper's construction is presented as satisfying it directly. With no further inconsistency located, the UNVERDICTED status is unaffected.","tokens_in":1710,"tokens_out":238,"duration_ms":38774,"concrete_test":"Extract the explicit response functions and ontic-state space of COM from §3 or §4; confirm that each observable has a unique outcome for every ontic state independent of apparatus parameters, then recompute the KS inequality violation on the same set of contexts used in the paper; if the violation disappears or device dependence appears, the separation fails.","verdict_should_be":"UNCHANGED","load_bearing_attack":"The central claim is that COM is a deterministic ontological model (outcomes fixed by ontic state alone) that nevertheless reproduces KS-contextual quantum statistics. The abstract states this is achieved by construction, with no indication of hidden device dependence or failure to match the required marginals. No internal inconsistency appears in the stated definitions of the two contextuality notions or in the claim that COM separates them.","agreement_with_reader":"agree"},"referee_report":{"model":"grok-4.3","summary":"The paper claims that Kochen-Specker (KS) contextuality and Bohmian contextuality are distinct notions in hidden-variable theories. It shows that the Contextual Ontological Model (COM) from Hindlycke and Larsson (PRL 2022) reproduces KS-contextual quantum statistics while remaining fully deterministic: every allowed measurement outcome is fixed by the ontic state alone, with no additional dependence on measurement-device specifics. This is presented as a counterexample to the claim that Bohmian contextuality is required to enable KS contextuality, thereby allowing the two concepts to be studied independently.","tokens_in":1754,"tokens_out":356,"duration_ms":21191,"significance":"If the central claim holds, the result supplies a concrete, deterministic ontological model that separates KS contextuality from Bohmian contextuality. This strengthens the conceptual toolkit for analyzing contextuality by showing that device-dependent outcome assignment is not a necessary ingredient for reproducing KS-contextual marginals. The paper thereby opens the possibility of examining each notion on its own terms without conflating them.","major_comments":[],"minor_comments":[{"comment":"The abstract and introduction would benefit from a one-sentence reminder of the precise definition of Bohmian contextuality used in the COM construction (e.g., explicit reference to the relevant equation or section in the 2022 PRL).","section":"Abstract / §1"},{"comment":"A brief table or diagram contrasting the two contextuality notions (KS vs. Bohmian) with respect to outcome determination would improve readability for readers unfamiliar with the COM framework.","section":"§2"}],"recommendation":"accept","confidential_remarks":null},"author_rebuttal":{"model":"grok-4.3","summary":"We thank the referee for the positive assessment of our manuscript and the recommendation to accept. The referee's summary correctly identifies the central result: that the Contextual Ontological Model provides a deterministic hidden-variable theory reproducing KS-contextual statistics without Bohmian contextuality.","responses":[],"tokens_in":1240,"tokens_out":70,"duration_ms":20107,"standing_objections":[]},"desk_editor":{"model":"grok-4.3","letter":"The main point is that the COM model produces KS-contextual quantum statistics while keeping every allowed measurement outcome fixed by the ontic state alone, with no extra dependence on the measurement device. This undercuts the earlier claim that Bohmian contextuality is necessary.\n\nThe paper's contribution is the explicit separation. It takes the Contextual Ontological Model from the 2022 PRL and checks that it satisfies the KS requirement without the Bohmian feature. Outcomes are determined by the model state for all measurements the model permits, yet the statistics still match the contextual quantum predictions. That distinction is new and lets the two ideas be examined independently.\n\nThe definitions are laid out plainly and the argument follows from the model's construction. The paper does a straightforward job showing how the properties line up differently for each notion of contextuality.\n\nThe result rests on COM being a valid deterministic hidden-variable model that gets the marginals right. Any gap there would affect this claim too, but the logic presented does not introduce new inconsistencies. That dependence on prior work is the main limitation, and it looks minor given how the model was set up.\n\nThis is for readers working on quantum foundations and ontological models who want to sort through contextuality variants. It gives a concrete case that clarifies a point previously claimed the other way.\n\nIt deserves peer review. The counterexample is specific and the separation is useful enough to check in detail.","headline":"COM gives a direct counterexample showing Bohmian contextuality is not required for KS contextuality.","tokens_in":2176,"tokens_out":353,"would_cite":false,"duration_ms":30411,"reading_group":"maybe","serious_thinker":"yes","would_accept_peer_review":true},"rs_alignment":null,"lean_confirmation":null,"pith_extraction":{"msc":[],"pacs":[],"model":"grok-4.3","headline":"A hidden-variable model can produce Kochen-Specker contextuality while determining every measurement outcome from the ontic state alone.","keywords":["quantum contextuality","Kochen-Specker theorem","Bohmian mechanics","hidden-variable models","ontological models","contextual ontological model"],"falsifier":"An explicit calculation or simulation showing that some measurement allowed by the COM rules yields an outcome not fixed by the ontic state, or that the COM fails to reproduce a KS-contextual correlation in a concrete finite-dimensional system.","tokens_in":2614,"feed_emoji":"⚛","tokens_out":632,"duration_ms":26281,"temperature":0.7,"pith_summary":"The paper establishes that Bohmian contextuality, in which some outcomes depend on apparatus details beyond the model state, is not required to obtain Kochen-Specker contextuality in a hidden-variable theory. The Contextual Ontological Model achieves the KS predictions while ensuring every allowed measurement outcome is fixed by the ontic state. This separation shows the two notions of contextuality are logically independent. A sympathetic reader would care because it removes an assumed link between distinct flavours of contextuality and opens the possibility of studying them in isolation.","feed_headline":"Hidden-variable model yields KS contextuality without Bohmian contextuality","feed_subtitle":"The Contextual Ontological Model fixes every outcome by the ontic state while still reproducing Kochen-Specker predictions, separating the t","key_machinery":"The Contextual Ontological Model (COM), a hidden-variable theory that reproduces quantum KS-contextual predictions while keeping all measurement outcomes fully determined by the ontic state.","core_discovery":"The recently proposed Contextual Ontological Model produces KS contextual predictions but does not have the Bohmian contextuality; the outcome of every measurement allowed by COM can be predicted from the model state itself. This distinguishes Bohmian contextuality from KS contextuality, and enables individual study of the two concepts.","pith_inferences":["Similar constructions might separate other pairs of contextuality or nonlocality notions that are currently conflated.","Experimental tests could focus on KS inequalities while enforcing strict device independence to isolate the KS component.","The existence of such models suggests that proofs requiring Bohmian contextuality to obtain KS contextuality rest on an extra assumption not forced by quantum theory itself."],"forward_implications":["KS contextuality can appear in ontological models that lack any device-dependent outcome assignment.","The two contextuality notions can be investigated independently in the same framework.","COM supplies a concrete counter-example to any claim that Bohmian-style contextuality is necessary for KS contextuality.","All measurements permitted by COM remain deterministic functions of the ontic state."],"fun_headline_variants":["COM produces KS contextuality without Bohmian contextuality","Hidden-variable model has KS contextuality but no Bohmian type","KS contextuality decoupled from Bohmian in ontological model","COM shows KS contextuality without any Bohmian contextuality"],"cache_read_input_tokens":2112,"weakest_assumption_plain":"That the COM is a valid hidden-variable model that exactly reproduces the quantum predictions required for KS contextuality while fixing every outcome by the ontic state.","fun_headline_variants_meta":{"raw":{"variants":["COM produces KS contextuality without Bohmian contextuality","Hidden-variable model has KS contextuality but no Bohmian type","KS contextuality decoupled from Bohmian in ontological model","COM shows KS contextuality without any Bohmian contextuality"]},"model":"grok-4.3","cost_usd":0.004131,"raw_usage":{"total_tokens":2091,"prompt_tokens":662,"num_sources_used":0,"completion_tokens":68,"cost_in_usd_ticks":41312000,"prompt_tokens_details":{"text_tokens":662,"audio_tokens":0,"image_tokens":0,"cached_tokens":256},"completion_tokens_details":{"audio_tokens":0,"reasoning_tokens":1361,"accepted_prediction_tokens":0,"rejected_prediction_tokens":0}},"tokens_in":662,"tokens_out":68,"duration_ms":10807,"temperature":1.0,"reasoning_tokens":1361,"cache_read_input_tokens":256,"cache_creation_input_tokens":0},"cache_creation_input_tokens":0},"created_at":"2026-06-30T13:34:00.560066+00:00","model_set":{"reader":"grok-4.3"},"falsifier":"An explicit calculation or simulation showing that some measurement allowed by the COM rules yields an outcome not fixed by the ontic state, or that the COM fails to reproduce a KS-contextual correlation in a concrete finite-dimensional system.","supporting_citations":[],"review_version":1}