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arXiv · 1701.03767

Analysis of Coupled Scalar Systems by Displacement Convexity

Rafah El-Khatib·Nicolas Macris·Tom Richardson·Rüdiger Urbanke
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Abstract

Potential functionals have been introduced recently as an important tool for the analysis of coupled scalar systems (e.g. density evolution equations). In this contribution, we investigate interesting properties of this potential. Using the tool of displacement convexity, we show that, under mild assumptions on the system, the potential functional is displacement convex. Furthermore, we give the conditions on the system such that the potential is strictly displacement convex, in which case the minimizer is unique.

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Rafah El-Khatib, Nicolas Macris, Tom Richardson, Rüdiger Urbanke. 2017-01-13. Analysis of Coupled Scalar Systems by Displacement Convexity. https://arxiv.org/abs/1701.03767

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