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

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 نشر من قبل Richard Szabo
 تاريخ النشر 2007
  مجال البحث
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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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