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8
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An inverse to functional calculus
Given a Borel function f:R→R∪{∞}, functional calculus allows to calculate F(x) for any unbounded selfadjoint operator x on a Hilbert space H, ...
6
votes
1
answer
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Unbounded version of continuous functional calculus
For a normal operator T on a Hilbert space H, it is well known that for any continuous complex valued function f on the spectrum of T, we have a well-defined operator $f(T) \in B({\cal ...