Images of contractive projections on operator algebras
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چکیده
It is shown that if P is a weak∗-continuous contractive projection on a JBW∗-triple M , then P(M) is of type I or semifinite, respectively, if M is of the corresponding type. We also show that P(M) has no infinite spin part if M is a type I von Neumann algebra. 2002 Elsevier Science (USA). All rights reserved.
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تاریخ انتشار 2002