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arXiv · 1611.10099

Stability of the entropy equation

Eszter Gselmann
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Abstract

In this paper we prove that the so--called entropy equation, i.e., \[ H\left(x, y, z\right)=H\left(x+y, 0, z\right)+H\left(x, y, 0\right) \] is stable in the sense of Hyers and Ulam on the positive cone of $\mathbb{R}^{3}$, assuming that the function $H$ is approximatively symmetric in each variable and approximatively homogeneous of degree $\alpha$, where $\alpha$ is an arbitrarily fixed real number.

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Eszter Gselmann. 2016-11-30. Stability of the entropy equation. https://arxiv.org/abs/1611.10099

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