Search Results (148)

Physics describes evolution, causal structure, and measurement outcomes, but lacks an accepted physical account of why one outcome-conditioned quantum situation is actual as the present. This article develops a conditional account within the reconstruction program, which places a premetric relational layer prior to spacetime dynamics. Conventional evolution specifies how states are related once a state space, time parameter, and dynamical law are supplied; continued admissible reconstruction addresses the prior realization question of which identities, laws, and successor records can remain physically well defined. The Indefinite Reconstruction Stability Principle requires readable structures and laws to survive admissible continuation and to ignore unobservable distinctions. A present is proposed to be the outcome-conditioned quantum read-out of an IRSP-stable, history-bearing reconstruction boundary. Because the underlying relational record need not factorize, its read-out is generally entangled. Admissible successors are represented by a quantum instrument; one stable record sector and its conditioned state constitute the next present without an external observer. A worked qubit measurement and a Bell-pair example connect this architecture to standard laboratory quantum science. Given an operational event-identity bridge, positivity, normalization, exclusive additivity, and a Hilbert-space read-out, Gleason representation fixes the Born form conditionally. Linear history composition implies no genuine third-order successor interference. Proper ancestry inheritance supplies conditional acyclicity, stable small-step channels recover standard effective dynamics, and spacelike confluence replaces a preferred global simultaneity surface. The result is a reconstructional architecture of present actuality with explicit premises and failure conditions, but no fitted collapse rate or microscopic actualization threshold. Full article

Public generative artificial intelligence (GenAI)–student datasets invite contested links between AI intensity, usage style, and grades, yet many analyses treat predictive accuracy or significant coefficients as sufficient evidence while skipping prior achievement, co-outcome leakage checks, and absolute effect-size thresholds. This paper presents a construct-audit protocol that treats associational claim survival as a reproducible labeling task: a feature-role taxonomy, forbidden-feature gates, nested out-of-fold change-in-$R^2$ materiality thresholds, and operational labels (stable, vanished, artifact-born—the last defined but not positively observed here), with predictive models used as instruments rather than as the scientific product. On the public ai_student_impact_dataset, treated as a construct-audit sandbox (possibly synthetic or engineered; no campus-population or causal claims), a five-seed Ridge-primary run is used to validate those rules rather than to estimate GenAI effects: all eight primary intensity and style claims are non-material under locked absolute gates (AI joint change-in-$R^2\approx 0.0064$ versus prior grade-point-average lift $\approx 0.859$), while a kitchen-sink OLS significance foil stars $12/19$ coefficients that the inventory does not promote. A report-only Random Forest check shows that style and joint-block clearance can depend on the modeling instrument; inventory labels remain Ridge-primary under the locked metric. The protocol can therefore withhold GenAI–GPA claims when absolute gates fail, and a six-step laptop workflow is specified so educational researchers can apply the same checks without reproducing the full validation schedule. Full article

I estimate the size of expected Born rule violation for a two-level superconducting qubit with dispersive readout. The estimate is based on extrapolating from an earlier analysis of experimental data on cloud chamber detection. That analysis made no explicit use of quantum measurement axioms and found an indication that the Born rule breaks down when it would otherwise naively predict extremely small measurement probabilities or probability densities. In such cases, the Born rule significantly over-predicts the number of measurement events. The level of breakdown that I estimate here for the two-level qubit may be too small to have a meaningful impact on practical quantum computing. Full article

Classical approaches often treat interaction as engineered product terms or as emergent patterns in flexible models, offering little control over how synergy or antagonism arises. We take a quantum-inspired view: following the Born rule (probability as squared amplitude), coherent aggregation sums complex amplitudes before squaring, creating an interference cross-term, whereas an incoherent proxy sums squared magnitudes and removes it. Representing input contributions as complex amplitudes, the relative phase between amplitudes modulates the sign and magnitude of this cross-term, providing a mechanism-level account of synergy versus antagonism. In a minimal amplitude-linear model over a $2\times 2$ design—the simplest setting for feature interaction—this cross-term equals the standard interaction contrast ${\Delta }_{\mathrm{INT}}$, which can be interpreted as the potential-outcome interaction measure under randomized assignment. We instantiate this idea in a lightweight Interference Kernel Classifier (IKC) and introduce two diagnostics: Coherent Gain (log-likelihood gain of coherent aggregation over the incoherent proxy) and Interference Information (the induced Kullback–Leibler gap). A controlled phase sweep recovers this identity. On a high-interaction synthetic task (XOR), IKC attains predictive performance closely matching that of the evaluated classical baselines under paired, budget-matched comparisons; on real tabular data, its competitiveness is dataset-dependent, trailing the best evaluated baseline on Adult while outperforming it on Bank Marketing. In coherent–incoherent ablations with learned parameters held fixed, removing the coherent cross-terms degrades negative log-likelihood, Brier score, and expected calibration error on both datasets, with positive Coherent Gain. This quantum-inspired approach offers an interpretable mechanism for modeling and diagnosing feature interactions in probabilistic classification. Full article

Classical evolutionary game theory rests on a hidden assumption: that an actor holds a definite strategy, pure or randomized, before it ever interacts. Yet human and organizational choices routinely violate this premise, displaying interference, order, and framing effects that classical probability cannot accommodate. We propose a framework in which an economic actor is genuinely undecided before market entry, modeled as a strategic superposition of pure strategies in a Hilbert space, and in which interaction acts as a measurement that collapses this state onto a realized strategy with Born-rule probabilities. Populations are described by a density operator whose diagonal carries strategy frequencies and whose off-diagonal coherences encode maintained superposition, evolving under a strategic master equation that couples coherent deliberation, decoherence in the strategy basis, and a replicator selection superoperator. Three results follow. A square-root representation places quantum normalization and evolutionary selection on a common geometric footing; the classical replicator equation emerges exactly as the strong-decoherence limit, with an explicit error bound; and strategy realization becomes basis-dependent through interference that no classical mixture reproduces. In a two-strategy market game, coherent coupling displaces the evolutionarily stable strategy by order Δ²/γ, recovering the classical value as decoherence dominates. The construction formalizes constitutive self-opacity and links bounded rationality to quantum interference, positioning classical evolutionary dynamics as one limiting regime of a broader strategic dynamics. Full article

We develop a comparative synthesis of quantum-information geometry beyond complex numbers, with emphasis on what different algebraic frameworks contribute to information-processing structure rather than on their formal novelty alone. The organizing idea is a layer-by-layer test of the standard complex Hilbert-space formalism: each non-complex or deformed framework modifies the scalar field, phase group, projective state space, Born-probability semantics, composition rule, measurement geometry, symmetry algebra or representation category. The central thesis is that such frameworks are physically meaningful when they identify which assumptions make complex quantum mechanics operationally stable: positive probabilities, associative multipartite composition, reversible dynamics, experimentally testable phases, locality constraints, informationally complete measurements, error bases and clear operational semantics. Real quantum theory probes the necessity of complex phases and local tomography; quaternionic quantum mechanics probes non-Abelian phase while retaining associativity and admitting complex embeddings; octonionic proposals probe the boundary where exceptional geometry survives but generic circuit composition is obstructed by non-associativity; Jordan algebras test ordered probabilistic state spaces; Clifford algebras and Bott periodicity provide the spinorial and topological grammar connecting gates, Hopf maps and periodic dimensions; and quantum-group or q-deformed constructions probe coproducts, braiding and representation categories rather than scalar amplitudes. We distinguish three roles that are often conflated: genuine hypercomplex kinematics, Hopf-fibration coordinates for ordinary complex multipartite entanglement, and deformed algebraic or categorical structures. The resulting map separates established equivalence and experimental-constraint results from useful representation tools and speculative programs, while identifying concrete open problems for non-complex quantum information. Full article

We present a vacuum-assisted Polymethyl methacrylate (PMMA) impregnation process for cotton textiles, coupled with a physics-aware bidirectional artificial neural network (ANN) framework, to both predict and tune the natural fiber composite response from a compliant and flexible to a stiff and strong behavior. Cotton fabric samples were impregnated with acetone-borne PMMA baths, ranging from 0 to 5 wt.% polymer concentration. After drying, the PMMA formed conformal fiber coatings and inter-fiber bridges, with optimal load transfer observed at approximately 0.5–1.0 wt.%. Mechanical properties, including the elastic modulus, tensile strength, ductility, and toughness, were measured alongside Differential Scanning Calorimetry (DSC), Glass Transition Temperature (T_g), Change in heat capacity at constant pressure (ΔCp), gravimetry, and morphology tests. Rule-of-mixtures, porosity, and thermal constraints were embedded as regularization within the ANN loss functions to improve the physical consistency of the training. The forward and inverse models achieved sub-percent prediction errors with narrow bootstrap confidence intervals. It was found that removing physics regularization notably increases forward model error (by fivefold), as well as the inverse model error by one order of magnitude. Full article

Bell’s theorem rules out developing a locally causal theory to describe quantum phenomena. Many take this to imply that any model of quantum entanglement must employ variables (called beables by Bell) which follow nonlocal rules, even though signaling is local. The alternative is to adopt an all-at-once (block universe) approach, with beables which may depend on both past and future inputs, even though signaling is causal. Within this lenient-causality approach (a.k.a. retrocausal), simple cases of entanglement have been successfully described by locally mediated stochastic toy models, i.e., toy models which are local in a sense which generalizes Bell’s local causality. Developing a widely applicable reformulation of quantum mechanics along these lines is a grand challenge. This work presents a general framework for such models and theories, and identifies the corresponding ontic and epistemic states. The epistemic state is closely analogous to the quantum state, yielding an explanation for the collapse of the wavefunction. In the case of the models of the framework, it is clear what the information is about. The expression for the empirically verifiable predictions of the models in terms of the ontic and epistemic states displays remarkable parallels to the Born rule. A toy-model example is discussed. Full article

In this paper we study photon entanglement in the framework of Maxwell–Schwartz field theory. The ambient state space is the complex Maxwellian distribution space $W={\mathcal{S}}^{\prime }({\mathbb{M}}_4,{\mathbb{C}}^3)$, whose elements are fields of the form $F=\overrightarrow{E}+ic\overrightarrow{B}$. Polarization is realized as a two-dimensional complex subspace of W, generated by suitable linearly polarized Maxwellian solutions associated with opposite propagation directions. This yields canonical polarization sectors $P_A$ and $P_B$, each naturally isomorphic to ${\mathbb{C}}^2$. Within this setting, the Bell singlet state is represented by a non-factorizable tensorial Maxwellian field in $P_A\otimes P_B\subset W\otimes W$. By means of the induced rotated polarization bases, the standard joint probabilities of the photon polarization experiment are recovered exactly, and the correlation law $E(a,b)=-cos\left(2\right(a-b\left)\right)$ is obtained. Consequently, the usual CHSH value $2\sqrt{2}$ is reproduced in the Maxwell–Schwartz framework. To clarify the meaning of this violation, we first formulate the CHSH inequality in a purely measure-theoretic form, as a theorem about four correlators represented on a single probability space by bounded measurable functions. We then show that the correlators produced by the intrinsic Maxwellian Bell state do not admit such a common representation. The obstruction is structural: the ontic state is a global non-product field configuration, and the four correlations arise from different polarization resolutions of the same tensorial Maxwellian state. A second main result concerns the Born rule. For $L^2$ scalar quantum states in the domain of the Maxwellian correspondence, we prove that the squared Hilbert norm, times the constant ${\epsilon }_0$, coincides with the electromagnetic energy of the associated field. This leads to an energy interpretation of the Born rule: the Born probability density is identified with the normalized electromagnetic energy density up to an interference term depending on the chosen Maxwell–Schwartz isomorphism, which assumes the role of a quantum context. In the context of the Aspect and collaborators’ experiment, we prove that, on the other hand, the polarization probabilities become energy contributions of the corresponding field components. These results show that photon entanglement, Bell inequality violation, and the Born rule admit a coherent interpretation within Maxwell–Schwartz field theory, where the basic ontological objects are electromagnetic-like fields rather than abstract state vectors. Full article

The use of Bohmian mechanics as a practical tool for modeling non-relativistic quantum phenomena of matter provides clear evidence of its success, not only as a way to interpret the foundations of quantum mechanics, but also as a computational framework. In the literature, it is frequently argued that such a realistic view—based on deterministic trajectories—cannot account for phenomena involving the “creation” and “annihilation” of photons. In this paper, by revisiting and rehabilitating earlier proposals, we show how quantum optics can be modeled using Bohmian trajectories for electrons in physical space, together with well-defined electromagnetic fields evolving in time. By paying special attention to an experimental scenario demonstrating partition noise for photons, and to how the Born rule emerges in this context, the paper pursues two main goals. First, it validates the use of this simple Bohmian framework for pedagogical and computational purposes in understanding and visualizing quantum electrodynamics phenomena. Second, given that measurements are ultimately indicated on matter pointers, it clarifies what it means to measure photon or electromagnetic-field properties, even when they are considered non-ontic elements. Full article

A classical fluid splitter produces the same patterns of energy redistribution as a Stern–Gerlach quantum device, with rotationally invariant coefficients of correlation between molecular paths. Alternative settings express a cosine squared relationship, leading to Tsirelson-type Bell violations with outcome independence. This result confirms the Correspondence Principle of quantum mechanics, where individual detection events express system-level properties according to Born’s Rule. Kochen–Specker contextuality and Bell Locality are not formally contradicted, but their interpretation is in question. Current definitions of “Local Realism” are limited to intrinsic particle properties. In contrast, quantum-like correlations require the acknowledgement of ensemble effects on dynamically inseparable entities, even when those entities are observed one at a time. Full article

We present Quantum-Informational History Optimization Theory (QIHOT) as a formal proposal for selecting a single realized quantum history from a space of dynamically admissible histories subject to boundary constraints. In the present paper, we restrict attention to finite-dimensional and toy-model settings, where the framework can be stated explicitly. QIHOT separates two levels: a dynamical prior over admissible histories generated by standard quantum evolution, and an informational selection rule that reweights those histories by an entropy-based cost functional. Within this structure, we show that standard Born statistics are recovered in symmetric-cost measurement scenarios when the prior is the usual Hilbert-space quantum prior. We further formulate conditions under which operational no-signaling is preserved, provided the selection functional factorizes locally for spacelike-separated regions. A fully worked two-outcome model illustrates how the framework interpolates between coherent evolution and measurement-like branch selection. We contrast QIHOT with the Many-Worlds Interpretation, the Transactional Interpretation, the Consistent Histories formalism, the Schwinger–Keldysh formalism, and Lagrangian-based retrocausal models, highlighting structural similarities and key differences. We emphasize that the present paper develops QIHOT as a scoped formal proposal with partial consistency results rather than as a complete replacement for quantum theory. Possible extensions to consciousness and cosmology are deferred to brief outlook-level discussion. Full article

Laser powder bed fusion (LPBF) can fabricate intricate metal components but is prone to defects, such as porosity and cracks, that degrade performance. We present an in situ monitoring framework that fuses structure-borne acoustic emission (AE) and coaxial two-color pyrometry acquired synchronously at 1 MHz. Modality-specific encoders are pretrained separately, their latent representations are exported, and a lightweight feature-level fusion classifier with two binary heads predicts crack-like and porosity-like indications. Evaluation uses a held-out grouped experiment/build-machine-part split with independent Archimedes density and micro-CT ground truth. On the held-out test set, the fused model achieved F1 = 0.974 for crack-like detection and F1 = 0.987 for porosity-like detection, with AUROC = 0.998 and 0.993, respectively. Recall was 1.00 for both heads, corresponding to false-positive rates of 11.18% for crack-like and 0.945% for porosity-like indications. These results support synchronized AE-pyrometry fusion as a promising high-sensitivity in situ screening approach for LPBF. A later matched within-framework ablation campaign was also performed under stricter checkpoint-screening rules to compare AE + PY + Aux, AE + PY, AE-only, and PY-only variants under a common grouped-split protocol. Together, these results support multimodal monitoring while highlighting the need for explicit coupon/geometry-stratified reporting and for separately architecture-optimized unimodal baselines. Full article

The Kirkwood–Dirac (KD) quasiprobability distribution describes any quantum state with respect to the eigenbases of two incompatible observables. While the KD quasiprobability distribution behaves similarly to a classical probability distribution, it can take on negative or nonreal values. Recently, the framework of the temporal Kirkwood–Dirac quasiprobability distribution has been proposed, generalizing the KD quasiprobability distribution to arbitrary multi-time quantum processes. In this work, we specifically focus on the temporal KD quasiprobability distribution within the context of two-time dynamics. We begin by constructing a nonclassicality measure derived from the real and imaginary parts of the temporal KD quasiprobability distribution. Next, we establish two uncertainty relations closely linked to this nonclassicality measure, one of which shows that the nonclassicality measure is bounded below by the measurement disturbance caused by the first measurement. Finally, we elucidate the relationships among temporal KD nonclassicality, the spatiotemporal Born rule, and spatiotemporal compatibility. Full article

Latino families in the United States experience persistent maternal and child health (MCH) inequities driven by a fragmented immigration and public benefits policy environment rather than inherent health differences. Although most Latino children are U.S.-born citizens, many live in mixed-status families in which immigration status determines eligibility for health care, nutrition assistance, and other essential services. This narrative policy review examines U.S. immigration and public benefit policies from 1965 to 2025 to assess how eligibility rules, enforcement practices, and policy instability shape access to maternal and child health services among Latino populations. Drawing on public health, legal, and social science literature, the review documents substantial variation in access to Medicaid, CHIP, nutrition programs, and emergency care by immigration status and state policy. Findings indicate that restrictive eligibility criteria, expansions and contractions of the public charge rule, and immigration enforcement practices have produced chilling effects that deter eligible families from accessing care, reduce prenatal and postpartum service utilization, and contribute to adverse birth outcomes and intergenerational health inequities. The review concludes that immigration policy functions as a structural determinant of MCH and identifies two key policy priorities: 1. maintaining the 2022 Final Public Charge Rule that excludes public safety-net programs, and 2. waiving the five-year Medicaid waiting period for all pregnant immigrants regardless of documentation status to ensure equitable access to essential maternal and child health care. Full article