International Journal of Functional Analysis, Operator Theory and Applications
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Abstract: Let be a bounded domain in with smooth boundary In
this paper, we investigate the spectral properties of a non-selfadjoint elliptic
differential operator acting
on Hilbert space with Dirichlet-type boundary conditions. Here and there exists such that Assume that where
Keywords and phrases: resolvent, asymptotic spectrum, distribution of eigenvalues, non-
selfadjoint, m-sectorial operator, completeness, summability of the Fourier series.
