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Harnack inequality for a class of degenerate elliptic operators

J. D. Fernandes·J. Groisman·S. T. Melo
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Abstract

We prove a Harnack inequality for a class of two-weight degenerate elliptic operators. The metric distance is induced by continuous Grushin-type vector fields. It is not know whether there exist cutoffs fitting the metric balls. This obstacle is bypassed by means of a covering argument that allows the use of rectangles in the Moser iteration.

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J. D. Fernandes, J. Groisman, S. T. Melo. 2003-02-06. Harnack inequality for a class of degenerate elliptic operators. https://arxiv.org/abs/math/0204186

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