S-wave absorption of scalars by noncommutative D3-branes

Abstract

On the supergravity side, we study the propagation of the RR scalar and the dilaton in the D3-branes with NS $B$-field. To obtain the noncommutative effect, we consider the case of $B\to \infty (\theta \to \pi /2)$. We approximate this as the smeared D1-brane background with $F_5=H=0$. In this background, the RR scalar induces an instability of the near-horizon geometry. However, it turns out that the RR scalar is nonpropagating, while the dilaton is a physically propagating mode. We calculate the s-wave absorption cross section of the dilaton. One finds ${\sigma }_0^{\varphi }{|}_{B\to \infty }\sim (\tilde{\omega }{\tilde{R}}_{\frac{\pi }{2}}{)}^{8.9}/{\omega }^5$ in the leading-order while ${\sigma }_0^{\varphi }{|}_{B=0}\sim (\tilde{\omega }{R}_0{)}^8/{\omega }^5$ in the D3-branes without $B$-field. This means that although the dilaton belongs to a minimally coupled scalar in the absence of $B$-field, it becomes a sort of fixed scalar in the limit of $B\to \infty$.

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References in corpus (10)

• String Theory and Noncommutative Geometry
• Large N Limit of Non-Commutative Gauge Theories
• Non-Commutative Yang-Mills and the AdS/CFT Correspondence
• On the Thermodynamics of Large N Noncommutative Super Yang-Mills Theory
• On the Hierarchy Between Non-Commutative and Ordinary Supersymmetric Yang-Mills
• Closed Strings Interacting with Noncommutative D-branes
• Supergravity with Self-dual B fields and Instantons in Noncommutative Gauge Theory
• Nonpropagation of tachyon on the BTZ black hole in type 0B string theory
• Scalar Absorption by Noncommutative D3-branes
• Tachyon and fixed scalars of D5${}_{\pm }$-D1${}_{\pm }$ black hole in type 0B string theory

Cited by in corpus (2)

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