000			a
999			_c33875 _d33875
008			250425b xxu||||| |||| 00| 0 eng d
020			_a9780521587105
082			_a515.7242 _bDAV
100			_aDavies, E. Brian
245			_aSpectral theory and differential operators
260			_bCambridge University Press, _c1996 _aCambridge :
300			_aix, 182 p. ; _bill., _c23 cm.
365			_b50.99 _c₤ _d116.70
504			_aIncludes bibliographical references and index.
520			_aThis book is an introduction to the theory of partial differential operators. It assumes that the reader has a knowledge of introductory functional analysis, up to the spectral theorem for bounded linear operators on Banach spaces. However, it describes the theory of Fourier transforms and distributions as far as is needed to analyse the spectrum of any constant coefficient partial differential operator. A completely new proof of the spectral theorem for unbounded self-adjoint operators is followed by its application to a variety of second-order elliptic differential operators, from those with discrete spectrum to Schrödinger operators acting on L2(RN). The book contains a detailed account of the application of variational methods to estimate the eigenvalues of operators with measurable coefficients defined by the use of quadratic form techniques. This book could be used either for self-study or as a course text, and aims to lead the reader to the more advanced literature on the subject.
650			_aBounded linear operator
650			_aDirichlet boundary conditions
650			_aDominated convergence theorem
650			_aEigenfunctions
650			_aElliptic operators
650			_aFriedrichs extension
650			_aHilbert space
650			_aNeumann boundary conditions
650			_aSpectral theorem
942			_2ddc _cBK