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arXiv · hep-th/9112014

N=2 Superstrings with (1,2m) Spacetime Signature

H. Lu·C. N. Pope·X. J. Wang·K. W. Xu
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Abstract

We show that the $N=2$ superstring in $d=2D\ge6$ real dimensions, with criticality achieved by including background charges in the two real time directions, exhibits a ``coordinate-freezing'' phenomenon, whereby the momentum in one of the two time directions is constrained to take a specific value for each physical state. This effectively removes this time direction as a physical coordinate, leaving the theory with $(1,d-2)$ real spacetime signature. Norm calculations for low-lying physical states suggest that the theory is ghost free.

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H. Lu, C. N. Pope, X. J. Wang, K. W. Xu. 1991-12-06. N=2 Superstrings with (1,2m) Spacetime Signature. https://doi.org/10.1016/0370-2693(92)90431-3

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