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Updated: Oct 5, 2025

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Exponentially Small Cosmological Constant in String Theory
Mehmet Demirtas1, Manki Kim1, Liam McAllister1
1Department of Physics, Cornell University, Ithaca, New York 14853, USA.
Abstract:
We construct a supersymmetric vacuum of string theory in which the magnitude of the vacuum energy is <10^{-123} in Planck units. The mechanism that we introduce generates a well-controlled exponential hierarchy from an appropriate choice of the quantized parameters in the superpotential. Our approach provides a new angle on the cosmological constant problem.
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