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Worldsheet Instantons and a Null String Limit of Born-Infeld Theory

Gerald A. Goldin·Nick E. Mavromatos·Richard J. Szabo
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Abstract

For a superstring theory in four spacetime dimensions, we propose a modification of the Born-Infeld action that possesses a well-defined tensionless limit. We interpret this as describing the effective target space dynamics of null strings on a D3-brane. We argue that such a modification can be induced by nonperturbative contributions from instantons in the worldsheet sigma-model describing string propagation on the brane.

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Gerald A. Goldin, Nick E. Mavromatos, Richard J. Szabo. 2007-04-05. Worldsheet Instantons and a Null String Limit of Born-Infeld Theory. https://doi.org/10.1140/epjc%2Fs10052-007-0474-5

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