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A bstract We argue for a relation between the supersymmetry breaking scale and the measured value of the dark energy density Λ. We derive it by combining two quantum gravity consistency swampland constraints, which tie the dark energy density Λ and the gravitino mass M 3 / 2 , respectively, to the mass scale of a light Kaluza-Klein tower and, therefore, to the UV cut-off of the effective theory. Whereas the constraint on Λ has recently led to the Dark Dimension scenario, with a prediction of a single mesoscopic extra dimension of the micron size, we use the constraint on M 3 / 2 to infer the implications of such a scenario for the scale of supersymmetry breaking. We find that a natural scale for supersymmetry signatures is $$ M=\mathcal{O}\left({\Lambda}^{\frac{1}{8}}\right)=\mathcal{O}\left(\textrm{TeV}\right). $$ M = O Λ 1 8 = O TeV . This mass scale is within reach of LHC and of the next generation of hadron colliders. Finally, we discuss possible string theory and effective supergravity realizations of the Dark Dimension scenario with broken supersymmetry.
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Dynamical dark energy and infinite statistics
In the Lambda-CDM model, dark energy is viewed as a constant vacuum energy density, the cosmological constant in the Einstein–Hilbert action. This assumption can be relaxed in various models that introduce a dynamical dark energy. In this paper, we argue that the mixing between infrared (IR) and ultraviolet (UV) degrees of freedom in quantum gravity leads to infinite statistics, the unique statistics consistent with Lorentz invariance in the presence of nonlocality, and yields a fine structure for dark energy. Introducing IR and UV cutoffs into the quantum gravity action, we deduce the form of Lambda as a function of redshift and translate this to the behavior of the Hubble parameter.
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- Award ID(s):
- 1821071
- PAR ID:
- 10492401
- Publisher / Repository:
- World Scientific
- Date Published:
- Journal Name:
- International Journal of Modern Physics A
- Volume:
- 37
- Issue:
- 17
- ISSN:
- 0217-751X
- Page Range / eLocation ID:
- 2242001
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1142/S0217751X22420015
