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تسجيل مستخدم جديدde Sitter Minima from M theory and String theory
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We study M-theory compactification on ${mathbb{T}^7/ mathbb{Z}_2^3}$ in the presence of a seven-flux, metric fluxes and KK monopoles. The effective four-dimensional supergravity has seven chiral multiplets whose couplings are specified by the $G_2$-structure of the internal manifold. We supplement the corresponding superpotential by a KKLT type non-perturbative exponential contribution for all, or for some of the seven moduli, and find a discrete set of supersymmetric Minkowski minima. We also study type IIA and type IIB string theory compactified on ${mathbb{T}^6/ mathbb{Z}_2^2}$. In type IIA, we use a six-flux, geometric fluxes and non-perturbative exponents. In type IIB theory, we use F and H fluxes, and non-geometric Q and P fluxes, corresponding to consistently gauged supergravity with certain embedding tensor components, emph{without non-perturbative exponents}. Also in these situations, we produce discrete Minkowski minima. Finally, to construct dS vacua starting from these Minkowski progenitors, we follow the procedure of mass production of dS vacua.
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