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String Interactions in PP-Waves

Rajesh Gopakumar
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Abstract

We argue that string interactions in a PP-wave spacetime are governed by an effective coupling $g_{eff}=g_s(μp^+\apm)f(μp^+ \apm)$ where $f(μp^+ \apm)$ is proportional to the light cone energy of the string states involved in the interaction. This simply follows from generalities of a Matrix String description of this background. $g_{eff}$ nicely interpolates between the expected result ($g_s$) for flat space (small $μp^+\apm$) and a recently conjectured expression from the perturbative gauge theory side (large $μp^+\apm$).

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Rajesh Gopakumar. 2002-05-16. String Interactions in PP-Waves. https://doi.org/10.1103/physrevlett.89.171601

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