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Order units in a C*-algebra

Anil K. Karn
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Abstract

Order unit property of a positive element in a $C^{*}$-algebra is defined. It is proved that precisely projections satisfy this order theoretic property. This way, unital hereditary $C^{*}$-subalgebras of a $C^{*}$-algebra are characterized.

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Anil K. Karn. 2003-12-05. Order units in a C*-algebra. https://arxiv.org/abs/math/0312120

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