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arXiv · 1509.06631

Differential Equations with a Difference Quotient

Brian Street
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Abstract

The purpose of this paper is to study a class of ill-posed differential equations. In some settings, these differential equations exhibit uniqueness but not existence, while in others they exhibit existence but not uniqueness. An example of such a differential equation is, for a polynomial $P$ and continuous functions $f(t,x):[0,1]\times [0,1]\rightarrow \mathbb{R}$, \begin{equation*} \frac{\partial}{\partial t} f(t,x) = \frac{ P(f(t,x))-P(f(t,0))}{x}, \quad x>0. \end{equation*} These differential equations are related to inverse problems.

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Brian Street. 2017-01-02. Differential Equations with a Difference Quotient. https://arxiv.org/abs/1509.06631

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