Abstract
We prove some new a priori estimates for H 2-convex functions which are zero on the boundary of a bounded smooth domain Ω in a Carnot group \({\mathbb{G}}\) . Such estimates are global and are geometric in nature as they involve the horizontal mean curvature \({\mathcal{H}}\) of ∂Ω. As a consequence of our bounds we show that if \({\mathbb{G}}\) has step two, then for any smooth H 2-convex function in \(\Omega \subset {\mathbb{G}}\) vanishing on ∂Ω one has
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Supported in part by NSF Grant DMS-07010001.
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Garofalo, N. Geometric second derivative estimates in Carnot groups and convexity. manuscripta math. 126, 353–373 (2008). https://doi.org/10.1007/s00229-008-0182-y
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DOI: https://doi.org/10.1007/s00229-008-0182-y