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arXiv · 2512.16836

Revival Dynamics from Equilibrium States: Scars from Chords in SYK

Debarghya Chakraborty·Dario Rosa
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Abstract

We develop a novel framework to build quantum many-body scar states in bipartite systems characterized by perfect correlation between the Hamiltonians governing the two sides. By means of a Krylov construction, we build an interaction term which supports a tower of equally-spaced energy eigenstates. This gives rise to finite-time revivals whenever the system is initialized in a purification of a generic equilibrium state. The dynamics is universally characterized, and is largely independent of the specific details of the Hamiltonians defining the individual partitions. By considering the two-sided chord states of the double-scaled SYK model, we find an approximate realization of this framework. We analytically study the revival dynamics, finding rigid motion for wavepackets localized on the spectrum of a single SYK copy. These findings are tested numerically for systems of finite size, showing excellent agreement with the analytical predictions.

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Debarghya Chakraborty, Dario Rosa. 2026-04-02. Revival Dynamics from Equilibrium States: Scars from Chords in SYK. https://doi.org/10.21468/scipostphys.21.3.064

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