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arXiv · 2204.06419

Persistence of spectral projections for stochastic operators on large tensor products

Robert S MacKay
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Abstract

In this paper it is proved that for families of stochastic operators on a countable tensor product, depending smoothly on parameters, any spectral projection persists smoothly, where smoothness is defined using norms based on ideas of Dobrushin. A rigorous perturbation theory for families of stochastic operators with spectral gap is thereby created. It is illustrated by deriving an effective slow 2-state dynamics for a 3-state probabilistic cellular automaton. Some further potential applications are discussed.

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Robert S MacKay. 2022-04-13. Persistence of spectral projections for stochastic operators on large tensor products. https://arxiv.org/abs/2204.06419

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