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Optimal lower bounds for the spectrum of a second order linear differential equation with a p-integrable coefficient

Published online by Cambridge University Press:  14 November 2011

E. J. M. Veling
Affiliation:
Stichting Mathematisch Centrum, Kruislaan 413, 1098 SJ Amsterdam, The Netherlands

Synopsis

In this note the differential expression M[y] ≡ − y” + qy, q∈Lp(ℝ+) for some p ≧ l, is considered on [0,∞) together with the boundary condition either y(0) = 0 or y'(0) = 0. Lower bounds are given for the spectrum of the self-adjoint operators T generated by M[·] and these boundary conditions. The bounds depend on the Lp-norm of the coefficient q and they improve results of Everitt and Eastham. The bounds are optimal.

Type
Research Article
Copyright
Copyright © Royal Society of Edinburgh 1982

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References

1Eastham, M. S. P.. Semi-bounded second-order differential operators. Proc. Roy. Soc. Edinburgh Sect. A 72 (1974), 916.Google Scholar
2Everitt, W. N.. On the spectrum of a second order linear differential equation with a p-integrable coefficient. Applicable Anal. 2 (1972), 143160.CrossRefGoogle Scholar
3Levine, Howard A.. An estimate for the best constant in a Sobolev inequality involving three integral norms. Ann. Mat. Pura Appl. 124 (1980), 181197.CrossRefGoogle Scholar
4Rosen, Gerald. On the Fisher and the cubic-polynomial equations for the propagation of species properties. Bull. Math. Biol. 42 (1980), 95106.Google Scholar
5Nagy, Béla v. Sz.. Über Integralungleichungen zwischen einer Funktion und ihrer Ableitung. Ada Sci. Math. (Szeged) 10 (1941), 6474.Google Scholar