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Title: Large extra dimensions from higher-dimensional inflation
We propose the possibility that compact extra dimensions can obtain large size by higher-dimensional inflation, relating the weakness of the actual gravitational force to the size of the observable Universe. Solution to the horizon problem implies that the fundamental scale of gravity is smaller than 10 13     GeV , which can be realized in a braneworld framework for any number of extra dimensions. However, requirement of an (approximate) flat power spectrum of primordial density fluctuations consistent with present observations makes this simple proposal possible only for one extra dimension at around the micron scale. After the end of five-dimensional inflation, the radion modulus can be stabilized at a vacuum with positive energy of the order of the present dark energy scale. An attractive possibility is based on the contribution to the Casimir energy of right-handed neutrinos with a mass at a similar scale. Published by the American Physical Society2024  more » « less
Award ID(s):
2112527
PAR ID:
10540391
Author(s) / Creator(s):
;
Publisher / Repository:
APS
Date Published:
Journal Name:
Physical Review D
Volume:
109
Issue:
10
ISSN:
2470-0010
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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