Mikhail S. Agranovich
abstract:
This paper contains a short presentation of author's results on spectral 
properties of main boundary value problems for strongly elliptic second-order 
systems in bounded Lipschitz domains. We consider the questions on the 
completeness of root functions, on the summability of Fourier series with 
respect to them and on their basis property in spaces $H^s_p$ with indices $s, 
p$ close to $\pm 1, 2$. The complete presentation will be published elsewhere.
Mathematics Subject Classification: 35J57, 35P05, 35P10
Key words and phrases: Strongly elliptic system, Lipschitz domain, spectral problem, discrete spectrum, completeness of root functions, Abel-Lidskii summability