Full paper in PDF format:
$%J. Kališ and M. Milman, Symmetrization and Sharp Sobolev Inequalities in Metric Spaces , Rev. Mat. Complut. 22 (2009), no. 2, 499–515.%$
Symmetrization and Sharp Sobolev Inequalities in Metric Spaces
Jan KALIŠ and Mario MILMAN
Department of Mathematics
Florida Atlantic University
Boca Raton, Fl 33431 — USA
kalis@math.fau.edu  extrapol@bellsouth.net
Received: January 22, 2009
Accepted: March 6, 2009

ABSTRACT

We derive sharp Sobolev inequalities for Sobolev spaces on metric spaces. In particular, we obtain new sharp Sobolev embeddings and Faber-Krahn estimates for Hörmander vector fields.

Key words: Sobolev, embedding, metric, vector fields, symmetrization.
2000 Mathematics Subject Classification:
Primary: 46E30, 26D10.