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arXiv · 1302.4999

A certain critical density property for invariant Harnack inequalities in H-type groups

Giulio Tralli
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Abstract

We consider second order linear degenerate-elliptic operators which are elliptic with respect to horizontal directions generating a stratified algebra of H-type. Extending a result by Gutiérrez and Tournier for the Heisenberg group, we prove a critical density estimate by assuming a condition of Cordes-Landis type. We then deduce an invariant Harnack inequality for the non-negative solutions from a result by Di Fazio, Gutiérrez, and Lanconelli.

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Giulio Tralli. 2013-02-20. A certain critical density property for invariant Harnack inequalities in H-type groups. https://arxiv.org/abs/1302.4999

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