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arXiv · 2607.14220

Non-perturbative saturation of Krylov complexity, and its implications in quantum gravity

Andrew Lucas·Amit Vikram
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Abstract

We study the dynamics of Krylov state complexity in finite-dimensional quantum systems. Orthogonal polynomials built on a discrete energy spectrum crowd away from regions where the density of states is low at large Krylov index. The physical implication of this result is that, even using a minimalist Krylov state complexity which is defined over the entire spectrum, the Krylov complexity provably stops growing a little past the Heisenberg length in every low-energy state. This has interesting implications for the proposal that Krylov complexity is related to the wormhole length in 2D quantum gravity.

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Andrew Lucas, Amit Vikram. 2026-07-15. Non-perturbative saturation of Krylov complexity, and its implications in quantum gravity. https://arxiv.org/abs/2607.14220

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