We give a short overview of sub-Laplacians on Carnot groups starting from a result by Caccioppoli dated 1934. Then we show that sub-Laplacians on Carnot groups of step one arise in studying curvature problems for manifolds. We restrict our presentation to the cases of the Webster-Tanaka curvature problem for the sphere and of the Levi-curvature equation for strictly pseudoconvex functions.
@article{RLIN_2003_9_14_3_227_0,
author = {Ermanno Lanconelli},
title = {Nonlinear equations on Carnot groups and curvature problems for CR manifolds},
journal = {Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni},
volume = {14},
year = {2003},
pages = {227-238},
zbl = {1225.35059},
mrnumber = {2064269},
language = {en},
url = {http://dml.mathdoc.fr/item/RLIN_2003_9_14_3_227_0}
}
Lanconelli, Ermanno. Nonlinear equations on Carnot groups and curvature problems for CR manifolds. Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni, Tome 14 (2003) pp. 227-238. http://gdmltest.u-ga.fr/item/RLIN_2003_9_14_3_227_0/
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