• SHOURIJEH, B. TABATABAIE (Department of Mathematics Shiraz University)
  • Received : 2004.02.26
  • Published : 2004.12.25


In this paper the left regular representation and the reduced $C^*$-algebra for a commutative separative semigroup is defined. The universal representation, the reduced $C^*$-algebra and the full $C^*$-algebra for the additive semigroup $N^+$ are given. Also it is proved that $C*_r(N^+){\ncong}C^*(N^+)$.


Supported by : Chungbuk National University


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