Uniqueness and Nonexistence of Positive Solutions to Semipositone Problems
School of Mathematics and Statistics, University of Sydney Sydney, NSW2006, Australia e-mail: normd{at}maths.usyd.edu.au
Department of Mathematics, College of William and Mary Williamsburg, VA 23187, USA and School of Mathematics, Harbin Normal University Harbin, Heilongjiang 150080, PRC e-mail: shij{at}math.wm.edu
Received 23 June 2005. Revision received 2 December 2005.
We consider the uniqueness of the positive solution to a semilinear elliptic equation with Dirichlet boundary condition and the nonlinearity satisfying f(0)<0 and having asymptotic sublinear growth rate. A similar idea is also applied to the nonexistence of a positive solution to a superlinear problem. 2000 Mathematics Subject Classification 35J65 (primary), 35B40 (secondary).
The first author is partially supported by the Australia Research Council; the second author is partially supported by United States NSF grants DMS-0314736 and EF-0436318, College of William and Mary junior research leave, and an Overseas Scholar grant from Heilongjiang Province, China.