Analog Hawking Radiation on a 156-Qubit Superconducting Processor: Spatial Localization, Temporal Dynamics, and Multi-Universe Validation

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)

1. 156-qubit Hawking analog — Largest quantum simulation of analog Hawking radiation to date
2. 83.2× flux localization ratio — Order of magnitude above detection threshold (10×)
3. O(1) depth scaling — MHIL architecture enables 20→156 qubit scaling in constant depth
4. 91.6% shuffle validation — Rigorous statistical control ruling out marginal artifacts
5. Multi-scale reproducibility — Validated across Mini (20q), Medium (40q), Large (80q) configurations
6. 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)