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arXiv · hep-th/0210308

String theory and the Classical Stability of Plane Waves

D. Brecher·J. P. Gregory·P. M. Saffin
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Abstract

The presence of fields with negative mass-squared typically leads to some form of instability in standard field theories. The observation that, at least in the light-cone gauge, strings propagating in plane wave spacetimes can have worldsheet scalars with such tachyon-like masses suggests that the supergravity background may itself be unstable. To address this issue, we perform a perturbative analysis around the type IIB vacuum plane wave, the solution which most obviously generates worldsheet scalars with negative mass-squared. We argue that this background is perturbatively stable.

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D. Brecher, J. P. Gregory, P. M. Saffin. 2002-12-19. String theory and the Classical Stability of Plane Waves. https://doi.org/10.1103/physrevd.67.045014

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