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Borderline gradient estimates at the boundary in Carnot groups

Published online by Cambridge University Press:  02 December 2020

Ramesh Manna
Affiliation:
TIFR Centre for Applicable Mathematics, Sharada Nagar, Chikkabommasandra, Bangalore560065, India (ramesh@tifrbng.res.in; rameshmanna@iisc.ac.in)
Ram Baran Verma
Affiliation:
SRM University Amaravati, Andhra Pradesh522502, India (rambaran.v@srmap.edu.in; rambv88@gmail.com)

Abstract

In this article, we prove the continuity of the horizontal gradient near a C1,Dini non-characteristic portion of the boundary for solutions to $\Gamma ^{0,{\rm Dini}}$ perturbations of horizontal Laplaceans as in (1.1) below, where the scalar term is in scaling critical Lorentz space L(Q, 1) with Q being the homogeneous dimension of the group. This result can be thought of both as a sharpening of the $\Gamma ^{1,\alpha }$ boundary regularity result in [4] as well as a subelliptic analogue of the main result in [1] restricted to linear equations.

Type
Research Article
Copyright
Copyright © The Author(s), 2020. Published by Cambridge University Press on behalf of The Royal Society of Edinburgh

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