Continuity of the Polar Decomposition for Unbounded Operators on Hilbert C*-modules
نویسندگان
چکیده
For unbounded operators t, s between Hilbert C*-modules which admit the polar decompositions V|t|, W|s|, respectively, we obtain an explicit upper bound estimate for the gap between t and s in terms of the norm of the bounded operators V − W , C|t| − C|s| and C|t∗| − C|s∗|, where C|t| and C|s| are the Cayley transforms of |t| and |s|. The result are used to drive a criterion for continuity of the polar decomposition for unbounded operators between Hilbert C*-modules.
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