Let be an -type group and be its harmonic extension. We study a left invariant Hardy–Littlewood maximal operator on , obtained by taking maximal averages with respect to the right Haar measure over left-translates of a family of neighbourhoods of the identity. We prove that the maximal operator is of weak type .
@article{AMBP_2006__13_1_87_0, author = {Vallarino, Maria}, title = {A maximal function on harmonic extensions of $H$-type groups}, journal = {Annales math\'ematiques Blaise Pascal}, volume = {13}, year = {2006}, pages = {87-101}, doi = {10.5802/ambp.214}, zbl = {1137.43003}, mrnumber = {2233012}, language = {en}, url = {http://dml.mathdoc.fr/item/AMBP_2006__13_1_87_0} }
Vallarino, Maria. A maximal function on harmonic extensions of $H$-type groups. Annales mathématiques Blaise Pascal, Tome 13 (2006) pp. 87-101. doi : 10.5802/ambp.214. http://gdmltest.u-ga.fr/item/AMBP_2006__13_1_87_0/
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