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Interaction between Noncommutative Open String and Closed-String Tachyon

Akira Kokado·Gaku Konisi·Takesi Saito
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Abstract

We construct a vertex operator which describes an emission of the ground-state tachyon of the closed string out of the noncommutative open string. Such a vertex operator is shown to exist only when the momentum of the closed-string tachyon is subject to some constraints coming from the background $B$ field. The vertex operator has a multiplicative coupling constant $g(σ)$ which depends on $σ$ as $g(σ)=\sin^2 σ$ in $0 \le σ\le π$. This behavior is the same as in the ordinary B=0 case.

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Akira Kokado, Gaku Konisi, Takesi Saito. 2001-03-27. Interaction between Noncommutative Open String and Closed-String Tachyon. https://doi.org/10.1143/ptp.106.645

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