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arXiv · hep-th/9507063

S-Duality and Cosmological Constant in String Theory

S. Kar·J. Maharana·H. Singh
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Abstract

The S-duality invariance of the equations of motion of four dimensional string effective action with cosmological constant, $Λ$, is studied. It is demonstrated that the S-duality symmetry of the field equations are broken for nonzero $Λ$. The ``naturalness'' hypothesis is invoked to argue that $Λ$ should remain small since exact S-duality symmetry will force the cosmological constant to vanish in the string effective action.

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S. Kar, J. Maharana, H. Singh. 1996-02-13. S-Duality and Cosmological Constant in String Theory. https://doi.org/10.1016/0370-2693(96)00227-4

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