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Duality twists, orbifolds, and fluxes

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J. E. a By W y can can a presen prop useful e e mo kno H-flux. compactification y the v v is teresting ould a [3] [1] [2] wists, ha has ha of toroidal are lead whic one t The on here w all man w of relation tial minima the theoretic in Ac It Issac realistic References for JHEP09(2003)054 428 109 . 04 , d 11 Phys. B in gy 584 388 Nucl. gy massive avity , Phys. B ett. string (1995) gauge B gr duction 3 Ener L in Phys. e ory 995 er gy r Ener ls (2) onstant e-II ett. gy 438 c the L sup Phys. non-trivial High nine-dimensional SO typ wal Phys. Ener al B F (2001) High , ]. J. Ener (2002) of hep-th/0203146 gic e-II , om string with J. , 4 e and Phys. fr Nucl. 609 High , typ , , in ]. Phys. ]. High M dimensional B J. 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