Published online by Cambridge University Press: 09 August 2012
In this paper we consider the discreteness of spectrum for higher-order differential operators in weighted function spaces. Using the method of embedding theorems of weighted Sobolev spaces Hnp in weighted spaces Ls,r, we obtain a new sufficient and necessary condition to ensure that the spectrum is discrete, which can be easily used to judge the discreteness of some differential operators.
The work of the authors is supported by the National Nature Science Foundation of China (grant number 11161030) and Shandong Education Fund of College Scientific Research (grant number J12LI57).