Pointwise Approximation by Elementary Complete Contractions
نویسنده
چکیده
A complete contraction on a C-algebra A, which preserves all closed two sided ideals J , can be approximated pointwise by elementary complete contractions if and only if the induced map on B⊗A/J is contractive for every C-algebra B, ideal J in A and C-tensor norm on B ⊗ A/J . A lifting obstruction for such an approximation is also obtained.
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