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arXiv · 1008.2088

On active drains and causality

Paul Kinsler
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Abstract

The concept of an \emph{active drain} has been used recently to provide an optical element which manages to perfectly sink incoming electromagnetic radiation. Here I show that without prior knowledge of the incoming signal, an element attempting respond as an active localized drain cannot succeed.

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Paul Kinsler. 2014-08-01. On active drains and causality. https://doi.org/10.1103/physreva.82.055804

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