ArticleOriginal scientific text

Title

Note on semigroups generated by positive Rockland operators on graded homogeneous groups

Authors 1, 1, 1

Affiliations

  1. 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 pt 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 |p1(x)|Cexp(-cτ(x)d/(d-1)). Moreover, if G is not stratified, more precise estimates of p1 at infinity are given.

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Pages:
115-126
Main language of publication
English
Received
1993-03-29
Accepted
1993-10-25
Published
1994
Exact and natural sciences