Asymptotics of sums of subcoercive operators

A.F.M. Elst, ter, N. Dungey, D.W. Robinson

Research output: Contribution to journalArticleAcademicpeer-review


We examine the asymptotic, or large-time, behaviour of the semigroup kernel associated with a finite sum of homogeneous subcoercive operators acting on a connected Lie group of polynomial growth. If the group is nilpotent we prove that the kernel is bounded by a convolution of two Gaussians whose orders correspond to the highest and lowest orders of the homogeneous subcoercive components of the generator. Moreover we establish precise asymptotic estimates on the difference of the kernel and the kernel corresponding to the lowest order homogeneous component. We also prove boundedness of a range of Riesz transforms with the range again determined by the highest and lowest orders. Finally we analyze similar properties on general groups of polynomial growth and establish positive results for local direct products of compact and nilpotent groups.
Original languageEnglish
Pages (from-to)231-260
JournalColloquium Mathematicum
Issue number2
Publication statusPublished - 1999


Dive into the research topics of 'Asymptotics of sums of subcoercive operators'. Together they form a unique fingerprint.

Cite this