- partial isometry
- мат. частичная изометрия;
частично изометрический оператор
Большой англо-русский и русско-английский словарь. 2001.
Большой англо-русский и русско-английский словарь. 2001.
Partial isometry — In functional analysis a partial isometry is a linear map W between Hilbert spaces H and K such that the restriction of W to the orthogonal complement of its kernel is an isometry. We call the orthogonal complement of the kernel of W the initial… … Wikipedia
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Extensions of symmetric operators — In functional analysis, one is interested in extensions of symmetric operators acting on a Hilbert space. Of particular importance is the existence, and sometimes explicit constructions, of self adjoint extensions. This problem arises, for… … Wikipedia