We test whether the Hayden-Preskill scrambled black hole evaporation circuit produces the Page curve behavior it predicts. Running this circuit past the Page time on real hardware requires the black hole register to stay coherent across six evaporation steps, something qubit decoherence has prevented until now. CIQA, a 1: 5 quantum error correction code, makes this experiment possible for the first time. The Hayden-Preskill model predicts that within their scrambled mirror circuit, entropy rises then falls as inter-radiation correlations accumulate, even with a fixed-size black hole register. Across height independent runs on IBM heron r2, and three backends, we test both components of this prediction: the shape of the entropy curve the pairwise Renyi-2 mutual information between radiation qubits. In all height runs, entropy rises continuously through all six evaporation steps and does not fall past the Page time. Pairwise mutual information across 35 radiation qubit pairs per run remains consistent with zero at every time step. Within the Hayden-Preskill circuit model, neither component of the Page curve behavior is observed in the data. --------------------------------- Quantum error correction handled by CIQA - DOI: 10. 5281/zenodo. 19405503 Circuit routing and optimization handled by CIQS - DOI: 10. 5281/zenodo. 19056796 All data attached (PageCurveFullData. zip) --------------------------------- v3 This version introduces new runs, rounds some angles, comes with all the available data, and directly addresses the Hayden-Preskill paper that inspired it. -------------------------------- arcadialab. fr
Jessy Pensédent (Thu,) studied this question.