ArticleOriginal scientific text

Title

Norm continuity of c0-semigroups

Authors 1, 1

Affiliations

  1. Mathematisches Institut I, Universität Karlsruhe, Englerstr. 2, D-76128 Karlsruhe, Germany

Abstract

We show that a positive semigroup Tt on Lp(Ω,ν) with generator A and ||R(α + i β)|| → 0 as |β| → ∞ for some α ∈ ℝ is continuous in the operator norm for t>0. The proof is based on a criterion for norm continuity in terms of "smoothing properties" of certain convolution operators on general Banach spaces and an extrapolation result for the Lp-scale, which may be of independent interest.

Bibliography

  1. H. Alt, Lineare Funktionalanalysis, Springer, Berlin, 1992.
  2. J. Bergh and J. Löfström, Interpolation Spaces, Springer, Berlin, 1976.
  3. E. B. Davies, One-Parameter Semigroups, Academic Press, London, 1980.
  4. A. Driouich and O. El-Mennaoui, On the inverse formula of Laplace transforms, preprint.
  5. O. El-Mennaoui and K. J. Engel, On the characterization of eventually norm continuous semigroups in Hilbert space. Arc. Math. (Basel) 63 (1994), 437-440.
  6. O. El-Mennaoui and K. J. Engel, Towards a characterization of eventually norm continuous semigroups on Banach spaces, Quaestiones Math. 19 (1996), 183-190.
  7. J. Martinez and J. Mazon, C0-semigroups norm continuous at infinity, Semigroup Forum 52 (1996), 213-224.
  8. J. van Neerven, The Asymptotic Behaviour of Semigroups of Linear Operators, Birkhäuser, Basel, 1996.
  9. A. Pazy, Semigroups of Linear Operators and Applications to Partial Differential Equations, Springer, New York, 1983.
  10. L. Weis, A short proof for the stability theorem for positive semigroups on Lp(ν), Proc. Amer. Math. Soc. (1998), to appear.
  11. L. Weis, Integral operators and changes of density, Indiana Univ. Math. J. 31 (1982), 83-96.
  12. P. You, Characteristic conditions for c0-semigroups with continuity in the uniform operator topology for t>0, Proc. Amer. Math. Soc. 116 (1992), 991-997.
Pages:
169-178
Main language of publication
English
Received
1998-05-06
Accepted
1998-10-23
Published
1999
Exact and natural sciences