Proceedings of the Royal Society of Edinburgh Section A Mathematics

Positive extensions of automorphisms of spin factors

A. GUYAN ROBERTSON

Published Jan 1, 1983• 14 citations

Abstract

Synopsis A spin factor is a JW-factor of type I2. It is shown that certain automorphisms of finite dimensional spin factors extend to extremal positive linear maps on complex matrix algebras which are not decomposable, and hence, do not preserve extreme rays of the positive cone.

DOI: 10.1017/s0308210500016139

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