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arXiv · 1803.02440

A shift map with a discontinuous entropy function

Christian Wolf
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Abstract

Let $f:X\to X$ be a continuous map on a compact metric space with finite topological entropy. Further, we assume that the entropy map $\mu\mapsto h_\mu(f)$ is upper semi-continuous. It is well-known that this implies the continuity of the localized entropy function of a given continuous potential $\phi:X\to R$. In this note we show that this result does not carry over to the case of higher-dimensional potentials $\Phi:X\to R^m$. Namely, we construct for a shift map $f$ a $2$-dimensional Lipschitz continuous potential $\Phi$ with a discontinuous localized entropy function.

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Christian Wolf. 2018-03-06. A shift map with a discontinuous entropy function. https://arxiv.org/abs/1803.02440

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