✦ LIBER ✦

Square Powers of Singularly Perturbed Operators

✍ Scribed by Sergio Albeverio; Witold Karwowski; Vladimir Koshmanenko

Publisher: John Wiley and Sons
Year: 1995
Tongue: English
Weight: 866 KB
Volume: 173
Category: Article
ISSN: 0025-584X
DOI: 10.1002/mana.19951730102

No coin nor oath required. For personal study only.

✦ Synopsis

We use the method of self-adjoint extensions to define a self-adjoint operator A, as the singular perturbation of a given self-adjoint operator A by a singular operator T on a Hilbert space.

We also find the structure of a singular operator Q such that the singular perturbation of A' by Q satisfies (A2)? = (AT)2. We obtain the explicit form of Q in terms of A and T. A definition of the n-th power for strictly positive symmetric operators is also given.

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