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arXiv · 2602.15524

Observing quantum many-body dynamics in emergent curved spacetime using programmable quantum processors

Brendan Rhyno·Bastien Lapierre·Smitha Vishveshwara·Khadijeh Najafi·Ramasubramanian Chitra
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Abstract

We digitally simulate quantum many-body dynamics in emergent curved backgrounds using 80 superconducting qubits on IBM Heron processors. By engineering spatially varying couplings in the spin-$\frac12$ XXZ chain, consistent with the low-energy description of the model in terms of an inhomogeneous Tomonaga-Luttinger liquid, we realize excitations that follow geodesics of an effective metric inherited from the underlying spatial deformation. Following quenches from N\'eel and few-spin-flip states, we observe curved light-cone propagation, horizon-induced freezing in the local magnetization, and position-dependent oscillation frequencies set by the engineered spatial deformation. Despite strong spatial inhomogeneity, unequal-time correlators reveal ballistic quasiparticle propagation in the spin chain. These results establish large-scale digital quantum processors as a flexible platform for detailed and controlled exploration of many-body dynamics in tunable and synthetic curved spacetimes.

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Brendan Rhyno, Bastien Lapierre, Smitha Vishveshwara, Khadijeh Najafi, Ramasubramanian Chitra. 2026-02-17. Observing quantum many-body dynamics in emergent curved spacetime using programmable quantum processors. https://arxiv.org/abs/2602.15524

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