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2.—Semi-bounded Second-order Differential Operators

Published online by Cambridge University Press:  14 February 2012

M. S. P. Eastham
Affiliation:
Department of Mathematics, Chelsea College, University of London.

Synopsis

Differential operators generated by the differential expression My(x) = —y″(x)+q(x)y(x) in L2(0, ∞) are considered. It is assumed that

is bounded for all x in [0, ∞) and some fixed ω > 0. The operators are shown to be bounded below and an estimate for the lower bound is obtained in terms of q(x). In the case where q(x) is LP (0, ∞) for some p ≧ 1, the results are compared with recent ones of W. N. Everitt. Some comments are made on the best-possible nature of the results.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1974

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References

References to Literature

[1]Coddington, E. A. and Levinson, N., 1955. Theory of Ordinary Differential Equations. New York: McGraw Hill.Google Scholar
[2]Eastham, M. S. P., 1972. On a limit-point method of Hartman. Bull. Lond. Math. Soc, to appear.CrossRefGoogle Scholar
[3]Eastham, M. S. P., 1973. Spectral Theory of Periodic Differential Equations. Edinburgh: Scottish Academic Press.Google Scholar
[4]Everitt, W. N., 1972. On the spectrum of a second order linear differential equation with a p-integrable coefficient, Applicable Analysis, 2, 143160.CrossRefGoogle Scholar
[5]Everitt, W. N. and Chaudhuri, Jyoti, 1968. On the spectrum of ordinary second order differential operators Proc. Roy. Soc. Edinb., 68A, 95119.Google Scholar
[6]Glazman, I. M., 1965. Direct Methods of Qualitative Spectral Analysis of Singular Differential Operators. Jerusalem: I.P.S.T.Google Scholar
[7]Kato, T., 1952. Note on the least eigenvalue of Hill's equation, Q. Appl. Math., 10, 292294.CrossRefGoogle Scholar
[8]Titchmarsh, E. C., 1962. Eigenfunction Expansions, Part I, 2nd edn. O.U.P.Google Scholar
[9]Titchmarsh, E. C., 1958. Ibid., Part II. O.U.P.Google Scholar
[10]Wintner, A., 1951. On the non-existence of conjugate points, Am. J. Math., 73, 368380.CrossRefGoogle Scholar