The Sobolev inequality on the Heisenberg group and the Yamabe problem on CR manifolds (d'après travaux avec J. M. Lee)
We consider degenerated elliptic equations of the form Under suitable assumptions on , we obtain a characterization of Wiener type (involving weighted capacities) for the set of regular points for these operators. The set of regular points is shown to depend only on . The main tool we use is an estimate for the Green function in terms of .
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