On sums and products of unbounded operators in Hilbert space
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- by M. J. J. Lennon PDF
- Trans. Amer. Math. Soc. 198 (1974), 273-285 Request permission
Abstract:
The characteristic matrices (in the sense of Stone) of the sum and product of two closed linear operators in Hilbert space are found in terms of the characteristic matrix of each operator. From these, necessary and sufficient conditions for the domain of the sum or product to be dense are found, and a new simple condition for the density of the domain of the sum is proved. The ideas developed are applied to the direct integral decomposition of closed linear operators.References
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Additional Information
- © Copyright 1974 American Mathematical Society
- Journal: Trans. Amer. Math. Soc. 198 (1974), 273-285
- MSC: Primary 47A60; Secondary 47A99
- DOI: https://doi.org/10.1090/S0002-9947-1974-0350472-5
- MathSciNet review: 0350472