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F Theory Orientifolds, M Theory Orientifolds, and Twisted Strings

Julie D. Blum
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Abstract

Orientifolds of the type IIB superstring that descend from F theory and M theory orbifolds are studied perturbatively. One finds strong evidence that a previously ignored twisted open string is required in these models. An attempt is made to interpret the $J$ type torsion in F theory where one finds a realization of Gimon and Johnson's models which does not require these twisted strings. S-duality also provides evidence for these strings.

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Julie D. Blum. 1996-08-11. F Theory Orientifolds, M Theory Orientifolds, and Twisted Strings. https://doi.org/10.1016/s0550-3213(96)00652-9

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