We report a gate-based quantum circuit that implements a qubit-truncated analog of pair creation, inspired by Hawking radiation phenomenology, and demonstrate certified Bell nonlocality on IBM Quantum hardware (ibm_fez, Heron R2, 156 qubits). Using a two-mode squeezing (TMS) gate mapping |00⟩ to cos(θ/2)|00⟩ + sin(θ/2)|11⟩, we generate entangled pairs across a designated ‘horizon’ position in a 20-qubit chain.Main results: CHSH Bell parameter S = 2.290 ± 0.010 (29.8σ shot-noise; >22σ conservative with systematics), entanglement witness W = 2.838 ± 0.004, and Bell-state fidelity F(|Φ⁺⟩) = 96%. Bootstrap resampling (10,000 iterations) confirms robustness (100% of samples violate classical bounds).Important caveat: this is a protocol demonstration for gravity-inspired entanglement certification on NISQ hardware, not a faithful simulation of Hawking radiation (no thermal spectrum / vacuum structure).
We report a gate-based quantum circuit that implements a qubit-truncated analog of pair creation, inspired by Hawking radiation phenomenology, and demonstrate certified Bell nonlocality on IBM Quantum hardware (ibm_fez, Heron R2, 156 qubits). Using a two-mode squeezing (TMS) gate mapping |00⟩ to cos(θ/2)|00⟩ + sin(θ/2)|11⟩, we generate entangled pairs across a designated ‘horizon’ position in a 20-qubit chain.Main results: CHSH Bell parameter S = 2.290 ± 0.010 (29.8σ shot-noise; >22σ conservative with systematics), entanglement witness W = 2.838 ± 0.004, and Bell-state fidelity F(|Φ⁺⟩) = 96%. Bootstrap resampling (10,000 iterations) confirms robustness (100% of samples violate classical bounds).Important caveat: this is a protocol demonstration for gravity-inspired entanglement certification on NISQ hardware, not a faithful simulation of Hawking radiation (no thermal spectrum / vacuum structure).
Abstract Hawking radiation, predicted in 1974, establishes a fundamental bridge between quantum mechanics, general relativity, and thermodynamics. Direct observation remains impossible for astrophysical black holes (T_H ~ 10⁻⁸ K), motivating the development of analog systems. We report the first large-scale kinematic analog of Hawking radiation on a superconducting quantum processor, utilizing IBM Quantum Heron (ibm_fez, 156 qubits) with four spin chains deployed across calibration-verified low-noise regions. Our Multi-Horizon Interleaved Layout (MHIL) architecture enables up to four simultaneous 'Hawking universes' with O(1) circuit depth independent of system size, requiring zero SWAP gates through native heavy-hex topology exploitation. We demonstrate: (i) spatial localization of entanglement flux at the analog horizon with ratio F_h/F_far = 83.2× under optimized error mitigation (44.3× under standard reproducible conditions) (threshold: 1.8×); (ii) monotonic temporal dynamics with R² = 0.999; (iii) multi-chain reproducibility across three independent horizons; (iv) rigorous statistical validation showing 91.6% signal degradation under shuffle control (p < 0.001, Cohen's d = 4.7), supporting a physical origin of the observed correlations. IMPORTANT CLARIFICATION: This work demonstrates KINEMATIC (not thermodynamic) analog Hawking radiation. We observe spatial localization and pair correlation signatures consistent with the kinematic aspects of Hawking's prediction. We do NOT measure a thermal Planck spectrum, do NOT extract a Hawking temperature T_H, and do NOT achieve Bell-CHSH violation (S ≈ 0.4 < 2.0). These limitations are explicitly acknowledged. Extensions include the first non-integrable regime simulation (98 qubits, disorder strength W = 0.65) and preliminary exploratory evidence of analog wormhole cross-throat flux (48 qubits, 5/5 seeds validated, p = 0.031—this preliminary result requires confirmation with larger sample size). These results establish the viability of kinematic analog Hawking simulations on NISQ superconducting processors accessible via cloud, opening quantum gravity phenomenology to the broader research community without specialized infrastructure.
We report the first experimental observation of analog Hawking radiation signatures on a 156-qubit superconducting quantum processor (IBM Heron R2). Using a spatially-varying XY spin chain with engineered coupling profile J(x) = J₀[1 - κ·tanh((x-x_h)/w)], we create an analog event horizon where excitation transport is kinematically forbidden. Our Multi-Horizon Interleaved Layout (MHIL) architecture enables up to four simultaneous "Hawking universes" with O(1) circuit depth scaling, achieving 156-qubit operation in only 44 transpiled layers. We demonstrate: (i) spatial localization of entanglement flux at the analog horizon with ratio F_h/F_far = 83.2× under optimized error mitigation (44.3× under standard reproducible conditions); (ii) temporal causality with monotonic signal development (R² > 0.99); (iii) the characteristic ⟨XX⟩ ≈ -⟨YY⟩ anti-correlation signature (r = 0.997) consistent with squeezed pair production; and (iv) effective temperature scaling β ∝ 1/κ consistent with the Hawking relation. Statistical validation via shuffle control demonstrates 91.6% signal degradation under random bit permutation (p < 0.001), providing strong evidence that the observed signal relies on multi-qubit spatial correlations consistent with XY dynamics. Multi-scale validation across 20-80 qubits confirms 100% peak position accuracy at the horizon. We emphasize that our results demonstrate kinematic analogs—spatial localization and pair-correlation signatures—not thermodynamic Hawking temperature. The bond correlator F(link) = ⟨XX⟩ + ⟨YY⟩ serves as a transport proxy; Bell-CHSH analysis yields S ≈ 0.4 < 2, confirming correlations without certified entanglement. All experimental data, including IBM Quantum job identifiers, are provided for independent verification. Key Results (Bullet Summary for Cover Letter) 156-qubit Hawking analog — Largest quantum simulation of analog Hawking radiation to date 83.2× flux localization ratio — Order of magnitude above detection threshold (10×) O(1) depth scaling — MHIL architecture enables 20→156 qubit scaling in constant depth 91.6% shuffle validation — Rigorous statistical control ruling out marginal artifacts Multi-scale reproducibility — Validated across Mini (20q), Medium (40q), Large (80q) configurations Full transparency — All IBM Quantum job IDs provided for external verification PACS / Subject Codes 03.67.Ac (Quantum algorithms, protocols, and simulations) 04.70.Dy (Quantum aspects of black holes, evaporation, thermodynamics) 75.10.Pq (Spin chain models)
Abstract We investigate measurement-induced effects on trans-horizon correlations in dynamic quantum circuits executed on IBM's 156-qubit superconducting processor (ibm_fez, Heron r2 architecture). We engineer a 40-qubit spin chain with a spatially-varying XX + YY coupling profile that creates an analog horizon at position x h = 20, where coupling strength reaches a minimum. We define a correlation contrast metric C = ⟨σ x iσ x j⟩ horizon − ⟨σ x σ x ⟩ exterior and compare three conditions: (i) unitary Trotter evolution (baseline), (ii) mid-circuit measurement with reset on qubits near the horizon, and (iii) control measurement on distant qubits. Each circuit was executed with 16,384 shots. The near-horizon measurement produces a (56.5 ± 1.9)% reduction in correlation contrast (95% CI from n = 5000 bootstrap resamples), while the control preserves (87.8 ± 2.1)% of baseline. Two ablation experiments constrain interpretation: removing the reset operation yields only a (2.6 ± 1.2) percentage point change, indicating that projective measurement—not state reset—drives the effect. Crucially, moving the measured subset 4 links away from the horizon collapses the reduction to (6.5 ± 2.3)%, yielding an 8.2 ± 1.4 ratio that demonstrates strong spatial localization. We additionally performed a flat-spacetime control with uniform coupling J(x) = J max on ibm_torino (Heron r1, 133 qubits), obtaining a baseline contrast that collapses to a small residual near zero (C = − 0.015, 95% CI [− 0.029, − 0.002]), confirming that the spatial structure arises from the engineered coupling profile rather than generic measurement artifacts. These results establish that mid-circuit measurement near an engineered coupling minimum preferentially disrupts correlations across that boundary, a signature qualitatively consistent with information-theoretic models of horizon physics.
Many solid-state quantum platforms do not permit sharp, projective measurements but instead yield continuous voltage or field traces under weak, non-demolition readout. In such systems, standard Bell tests based on dichotomic projective measurements are not directly applicable, raising the question of how quantum nonlocality can be certified from continuous time-series data. Here we develop a general theoretical framework showing that Bell-CHSH inequality violation can be extracted from continuous, non-projective measurements without assuming any specific collapse model or phase distribution. We show that sufficiently long continuous measurements of a single entangled pair sample its internal phase-probability structure, enabling effective dichotomic observables to be constructed through phase-sensitive projections and coarse-graining. The resulting Bell correlator is governed by two experimentally accessible resources: intrinsic single-qubit phase spread and nonlocal phase locking between qubits. We benchmark the resulting estimator against conventional projective-measurement CHSH tests implemented via quantum-circuit simulations using Qiskit, finding quantitative agreement in the Bell-violating regime without parameter fitting. Classical deterministic correlations cannot violate the CHSH bound, whereas quantum phase-locked systems recover the nonlinear angular dependence characteristic of entanglement. Our results provide a practical route to demonstrating Bell nonlocality in platforms where measurements are inherently continuous and weak.
We investigate measurement-induced effects on trans-horizon correlations in dynamic quantum circuits executed on IBM's 156-qubit superconducting processor (ibm_fez, Heron r2 architecture). We engineer a 40-qubit spin chain with a spatially-varying XX + YY coupling profile that creates an analog horizon at position xh = 20, where coupling strength reaches a minimum. We define a correlation contrast metric C = ⟨σxiσxj⟩horizon − ⟨σxσx⟩exterior and compare three conditions: (i) unitary Trotter evolution (baseline), (ii) mid-circuit measurement with reset on qubits near the horizon, and (iii) control measurement on distant qubits. Each circuit was executed with 16,384 shots. The near-horizon measurement produces a (56.5 ± 1.9)% reduction in correlation contrast (95% CI from n = 5000 bootstrap resamples), while the control preserves (87.8 ± 2.1)% of baseline. Two ablation experiments constrain interpretation: removing the reset operation yields only a (2.6 ± 1.2) percentage point change, indicating that projective measurement—not state reset—drives the effect. Crucially, moving the measured subset 4 links away from the horizon collapses the reduction to (6.5 ± 2.3)%, yielding an 8.2 ± 1.4 ratio that demonstrates strong spatial localization. We additionally performed a flat-spacetime control with uniform coupling J(x) = Jmax on ibm_torino (Heron r1, 133 qubits), obtaining a baseline contrast that collapses to a small residual near zero (C = − 0.015, 95% CI [− 0.029, − 0.002]), confirming that the spatial structure arises from the engineered coupling profile rather than generic measurement artifacts. These results establish that mid-circuit measurement near an engineered coupling minimum preferentially disrupts correlations across that boundary, a signature qualitatively consistent with information-theoretic models of horizon physics.
Abstract Many solid-state quantum platforms do not permit sharp, projective measurements but instead yield continuous voltage or field traces under weak, non-demolition readout. In such systems, standard Bell tests based on dichotomic projective measurements are not directly applicable, raising the question of how quantum nonlocality can be certified from continuous time-series data. Here we develop a general theoretical framework showing that Bell–CHSH inequality violation can be extracted from continuous, non-projective measurements without assuming any specific collapse model or phase distribution. We show that sufficiently long continuous measurements of a single entangled pair sample its internal phase-probability structure, enabling effective dichotomic observables to be constructed through phase-sensitive projections and coarse-graining. The resulting Bell correlator is governed by two experimentally accessible resources: intrinsic single-qubit phase spread and nonlocal phase locking between qubits. We benchmark the resulting estimator against conventional projective-measurement CHSH tests implemented via quantum-circuit simulations using Qiskit, finding quantitative agreement in the Bell-violating regime without parameter fitting. Classical deterministic correlations cannot violate the CHSH bound, whereas quantum phase-locked systems recover the nonlinear angular dependence characteristic of entanglement. Our results provide a practical route to demonstrating Bell nonlocality in platforms where measurements are inherently continuous and weak.