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arXiv · hep-th/0306226

Superstrings in Graviphoton Background and N=1/2+3/2 Supersymmetry

Nathan Berkovits·Nathan Seiberg
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Abstract

Motivated by Ooguri and Vafa, we study superstrings in flat R^4 in a constant self-dual graviphoton background. The supergravity equations of motion are satisfied in this background which deforms the N=2 d=4 flat space super-Poincare algebra to another algebra with eight supercharges. A D-brane in this space preserves a quarter of the supercharges; i.e. N=1/2 supersymmetry is realized linearly, and the remaining N=3/2 supersymmetry is realized nonlinearly. The theory on the brane can be described as a theory in noncommutative superspace in which the chiral fermionic coordinates $θ^α$ of N=1 d=4 superspace are not Grassman variables but satisfy a Clifford algebra.

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Nathan Berkovits, Nathan Seiberg. 2003-06-30. Superstrings in Graviphoton Background and N=1/2+3/2 Supersymmetry. https://doi.org/10.1088/1126-6708%2F2003%2F07%2F010

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