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Title: Pixelated Dark Energy
Abstract

We study the phenomenology of a recent string construction with a quantum mechanically stable dark energy. A mild supersymmetry protects the vacuum energy but also allowsTeV scale superpartner masses. The construction is holographic in the sense that the 4D spacetime is generated from “spacetime pixels” originating from five‐branes wrapped over metastable five‐cycles of the compactification. The cosmological constant scales asin the pixel number. An instability in the construction leads to cosmic expansion. This also causes more five‐branes to wind up in the geometry, leading to a slowly decreasing cosmological constant which we interpret as an epoch of inflation followed by (pre‐)heating when a rare event occurs in which the number of pixels increases by an order one fraction. The sudden appearance of radiation triggers an exponential increase in the number of pixels. Dark energy has a time varying equation of state with, which is compatible with current bounds, and could be constrained further by future data releases. The pixelated nature of the Universe also implies a large‐lcutoff on the angular power spectrum of cosmological observables with. We also use this pixel description to study the thermodynamics of de Sitter space, finding rough agreement with effective field theory considerations.

 
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NSF-PAR ID:
10459544
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Fortschritte der Physik
Volume:
67
Issue:
11
ISSN:
0015-8208
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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