ArticleOriginal scientific text
Title
Note on semigroups generated by positive Rockland operators on graded homogeneous groups
Authors 1, 1, 1
Affiliations
- Mathematical Institute, University of Wrocław, Pl. Grunwaldzki 2/4, 50-384 Wrocław, Poland
Abstract
Let L be a positive Rockland operator of homogeneous degree d on a graded homogeneous group G and let be the convolution kernels of the semigroup generated by L. We prove that if τ(x) is a Riemannian distance of x from the unit element, then there are constants c>0 and C such that . Moreover, if G is not stratified, more precise estimates of at infinity are given.
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