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On Operator Sum and Product Adjoints and Closures

Published online by Cambridge University Press:  20 November 2018

Karl Gustafson*
Affiliation:
Department of Mathematics, University of Colorado at Boulder, Boulder, CO, U.S.A. e-mail: gustafs@euclid.colorado.edu
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Abstract

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We comment on domain conditions that regulate when the adjoint of the sum or product of two unbounded operators is the sum or product of their adjoints, and related closure issues. The quantum mechanical problem $\text{PHP}$ essentially selfadjoint for unbounded Hamiltonians is addressed, with new results.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 2011

References

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