Can possible information tasks explain the quantum bound on Bell correlations? We obtain a conditional bound, without assuming a quantum state space, and identify the additional task requirements that recover the quantum value. Homogeneous frequency limits and common calibration domains imply consistent exclusivity. Completing two-copy parity measurements with an “other” outcome gives a Bell bound controlled by the weights of these residual records. Marletto’s T2 supplies four aligned parity sectors. A missing domain then requires an extra distinguishable label. An upper bound on readable labels, stable under adjoining spectators, and a reversible setting interchange remove the residual records. No-hypersignaling supplies this capacity bound when the relevant preparations are accessible and local signaling dimensions match the label counts. The result separates measurement existence, domain coverage, and readout weights.
Can possible information tasks explain the quantum bound on Bell correlations? We obtain a conditional bound, without assuming a quantum state space, and identify the additional task requirements that recover the quantum value. Homogeneous frequency limits and common calibration domains imply consistent exclusivity. Completing two-copy parity measurements with an “other” outcome gives a Bell bound controlled by the weights of these residual records. Marletto’s T2 supplies four aligned parity sectors. A missing domain then requires an extra distinguishable label. An upper bound on readable labels, stable under adjoining spectators, and a reversible setting interchange remove the residual records. No-hypersignaling supplies this capacity bound when the relevant preparations are accessible and local signaling dimensions match the label counts. The result separates measurement existence, domain coverage, and readout weights.
From a finite event record to Bell correlations and their loss under recording A pair is prepared together, read at two separated instruments, and allowed to leave a material record. This paper builds the correlation law from a real source geometry in Artian's Quantum Traction Theory. Its source-to-access equation is pK(r,s∣a,b)=C(KΩ)C[(Πr(a)⊗Πs(b)⊗I)KΩ] Here C is an additive, basis-invariant event capacity, Omega is the normalized orientation-neutral two-channel source, K is a specified record contact, and the projectors select the two instrument outputs. A real quarter-turn and a qualified shared-reference composition generate the readout algebra. Capacity symmetry fixes its quadratic weight. A separately stated capacity-to-frequency condition connects that weight to laboratory counts. The correlation follows before the Bell comparison For a phase-compensated record contact with overlap g between its two normalized record profiles, the construction gives EK(a,b)=−azbz−g(axbx+ayby),0≤g≤1. The intact-source limit is E = -a dot b. The same calculation yields the fixed-setting and optimized Bell responses: S45=2(1+g),Sopt=21+g2. Fresh independent record contacts multiply their overlaps. The paper derives the repeated-contact law, a capacity-based overlap calibration, uncertainty bounds, and a protocol that separates calibration from the Bell observations being judged. A source-first account with an explicit dependency map A1 supplies event-time labels and the clock-angle correspondence; A4 supplies the real dial; A5-X supplies completed-event support, with its inherited A6/A7 conditions. The two-channel preparation, balanced composition, capacity symmetry, frequency bridge, and record coupling are printed separately. Each theorem states exactly which conditions it uses. The Access uncertainty commutator is treated as a distinct inherited algebraic premise, rather than inferred from Bell correlations. When a receiver follows the source Version 2.0 constructs a matched receiver rather than assigning its transformation by name. Preserving every probability of the stated bilinear contact forces its transport to be the conjugate of the source transport, up to an overall phase: ∣rTVTUs∣2=∣rTs∣2for all r,s⟹V=eiαU. A finite set of basis and sum probes certifies this relation. A robust extension converts imperfect probe probabilities into an operator-error bound. Finite clock and shift operations then produce the comparison loop L=M+ω(I−M),ω=e2πi/d. The matched sector cancels the comparison phase while the unmatched sector retains it. This is a joint comparison law; each local readout can remain incompatible. The paper identifies the binary loop's ambiguity, provides additional probes that distinguish it, and transfers the Bell correlations into a complete detector record when the original carrier is consumed. One contact, two observable roles A specified marker contact supplies both the Bell record overlap and a resolved weak-measurement instrument: γK0K1=sinθ,=diag(cos(θ/2),sin(θ/2)),=diag(sin(θ/2),cos(θ/2)). An independent replay executes this instrument on all 40,032 tree records in the public Feng and colleagues archive, reproducing every stored decoder success/failure score. The main five-setting batch contains 32,000 records; the complete archive has six settings. The reproduced job-cluster residual probabilities are p = 0.0188753 and p = 0.0442603, respectively. These diagnose modest tension with the ideal instrument under the stated retrospective covariance. The matched QTT and quantum representations make the same archival predictions, so this replay is not a significance test between them. The package preserves the complete source-first Bell construction and adds finite receiver certificates, physical transport-error bounds, a common-contact derivation, five vector figures, a twelve-item achievements ledger, and offline reproducibility materials. The next operational question is precise: which independently qualified physical contact fixes both the record overlap and the receiver comparison response? Dependencies: QTT Main Book; finite address-capacity counting; real source histories and composition; A1-CHSH spinor character; Observation as Access.
When initially disjoint observers later consult physical records, under what specified conditions should their readouts agree? This paper gives a sufficient, access-relative certification within standard quantum mechanics. This certification requires stable, repeatably readable labels, low accessible sensitivity to coherence between the corresponding outcome sectors, and, for distributed consultation, carriers encoding a common label. Sequential nondemolition readouts of a single carrier with orthonormal record labels produce memory registers whose product record-basis outcomes match with Born probability one, independently of coherence in the carrier. For disjoint carriers, if their accessible joint state is close in trace distance to the corresponding marginal of an ideal spectrum broadcast structure, disagreement is bounded by that distance and by the two local discrimination errors. In a two-outcome model, the relevant coherence belongs to the branch-bearing system-record state rather than the record-only marginal; defining dephasing and off-diagonal observables on that same space yields an interference bound. These results concern record statistics, not interpretation-neutral identity of first-person experiences or observer-independent reality. Applied to Extended Wigner’s Friend scenarios, they support ideal ask-the-friend agreement. That fixed-setting equality supplies neither the setting-indexed joint model required by Absoluteness of Observed Events in Local Friendliness nor Brukner’s common Boolean representation, and it does not entail Frauchiger and Renner’s distinct quantum certainty, inter-agent-consistency, and single-valuedness assumptions. The no-go results remain valid conditional consequences of those premises.
Claims of quantum advantage should remain robust even when classical strategies have access to side information correlated with the benchmark under evaluation, just as Bell certification must account for measurement dependence. We formalize such correlations as benchmark dependence, a task-level generalization of measurement dependence. For every bounded-reward task, we show that the optimal benchmark-dependent classical score obeys Sη≤min{1,Scl+η}, and construct a family of tasks that saturates this bound, showing that the linear dependence on η is tight without further assumptions. For repeated product tasks with roundwise dependence, we obtain the stronger multiplicative bound Sη(n)≤(ωc+η)n, and extend the framework to finite-sample data, mutual-information constraints, multipartite tasks, and correlations distributed along a causal path. Applying these results to aggregated IBM hardware data, we obtain positive raw-count cycle-product certificates of 0.0812 for CHSH and 0.2178 for Mermin--GHZ, while the nine-context magic-square construction remains uncertified; readout-mitigated values are reported separately as sensitivity estimates. We also analyze a non-Bell quantum-kernel benchmark, where a label-construction variable has measured conditional dependence ηλ(Y)=0.5, above the threshold ηreq=0.375, required to close the reported score gap, and yields perfect classical classification. The framework therefore converts a quantum--classical score separation into a quantitative lower bound on the benchmark-correlated classical information required to explain the score separation.
For finite-dimensional binary systems and their bipartite composites, this paper establishes a conditional representation chain from a physical–observation dual-axis structure to quantum Bell correlations. An observational fact is jointly generated by a complete physical state and a complete observation state. Additivity and associativity of coherent responses, two-sided cancellation, and a full circle group of scalar phase transport select C among finite-dimensional unital associative real response algebras. Reversible mixing then determines a Hermitian metric up to an overall positive factor. Normalized two-channel responses form S3, and quotienting by their common phase yields the rank-one observation-event space and, with an outcome label, the pure observation fiber S3/U(1)=CP1≃S2. The universal bilinear composite of two independent systems is C4. Probabilities are first assigned within complete measurement contexts. Events with the same response filter are operationally interchangeable, so the local assignments glue along the observation axis into a positive orthogonally additive measure on the full projection lattice. Gleason's theorem then gives the unique trace representation p(P∣x)=Tr(ρxP), while composite marginal consistency returns the trace pairing to each local binary fiber. Every two-qubit correlation therefore has the universal form Eρ(a,b)=aTTρb. Joint rotational invariance and perfect equal-axis anticorrelation uniquely fix Tρ=−I3, producing the singlet cosine law E=−a⋅b=−cosθ. Finally, the local commutators in the squared CHSH operator confine all realizable correlations to 22. Fine-measurement completeness supplies saturating directions, while sharp preparation and reversible covariance make the singlet accessible. Thus CP1, the Born pairing, the cosine correlation law, and the Tsirelson bound arise within one chain linking phase structure, independent composition, and cross-context probability consistency.
Bell nonlocality is the experimentally testable incompatibility between quantum correlations and explanations based on local hidden variables. Its significance now extends beyond the foundations of quantum mechanics: a Bell-inequality violation can certify entanglement, randomness, measurement incompatibility, and cryptographic security without requiring a detailed model of the devices producing the observed data. This article develops the mathematical structure of Bell experiments and explains its role in device-independent quantum information. Conditional probability distributions are classified into local, quantum, and no-signalling sets; the Clauser-Horne-Shimony-Holt inequality is derived, and its classical, quantum, and algebraic limits are distinguished. Tsirelson’s bound is obtained from the CHSH operator, while Popescu-Rohrlich correlations demonstrate that no-signalling alone does not identify the quantum set. The relation between entanglement and nonlocality is examined through local entangled states, hidden nonlocality, and activation. Nonlocal games, semidefinite relaxations, self-testing, certified randomness, and device-independent quantum key distribution are treated as operational consequences of Bell violation. Particular attention is given to entropy accumulation, finite-data security, loophole-free experiments, and the limitations of device independence. Bell nonlocality emerges as both a foundational separation between classical and quantum causal models and a quantitative resource for cryptographic and informational tasks.
Bell inequalities are commonly presented as abstract constraints derived from assumptions of locality and realism, while their violation in quantum mechanics is often regarded as a profound mystery. In this work I present an operational reconstruction of Bell correlations using a constraint-based framework in which all assumptions are made explicit and executable. By separating locality, factorization, signaling, contextuality, and nonlocal correlation into independently controllable components, I demonstrate numerically that Bell inequality violation arises if and only if joint probability factorizability is relaxed. Quantum correlations emerge as extremal, geometrically constrained solutions within a broader space of admissible correlations. No appeal is made to wavefunction collapse or Hilbert space axioms. The results clarify the precise content of Bell’s theorem and suggest that quantum nonlocality is best understood as a global consistency constraint rather than a dynamical influence.