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تسجيل مستخدم جديدQuantum Lift of Non-BPS Flat Directions
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We study N=2, d=4 attractor equations for the quantum corrected two-moduli prepotential $mathcal{F}=st^2+ilambda$, with $lambda$ real, which is the only correction which preserves the axion shift symmetry and modifies the geometry. In the classical case the black hole effective potential is known to have a flat direction. We found that in the presence of D0-D6 branes the black hole potential exhibits a flat direction in the quantum case as well. It corresponds to non-BPS $Z eq 0$ solutions to the attractor equations. Unlike the classical case, the solutions acquire non-zero values of the axion field. For the cases of D0-D4 and D2-D6 branes the classical flat direction reduces to separate critical points which turn out to have a vanishing axion field.
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