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arXiv · 2506.07613

Discontinuous observables as an obstruction for small essential spectral radius

Oliver Butterley·Daniel Smania
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Abstract

We show that for a very wide class of Banach spaces of functions on [0,1] there are intrinsic lower bounds for the essential spectral radius of the transfer operator associated to piecewise smooth expanding maps. The class of Banach spaces studied includes any reasonable space which permits discontinuities.

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Oliver Butterley, Daniel Smania. 2025-06-09. Discontinuous observables as an obstruction for small essential spectral radius. https://arxiv.org/abs/2506.07613

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