Compact Hyperbolic Extra Dimensions: Branes, Kaluza-Klein Modes and Cosmology
Nemanja Kaloper, John March-Russell, Glenn D. Starkman, Mark Trodden
TL;DR
It is shown that the spectrum of Kaluza-Klein modes is radically altered, which allows the early Universe to evolve normally up to substantial temperatures, and completely negates the astrophysical constraints on M(*.
Abstract
We reconsider theories with low gravitational (or string) scale M_* where Newton's constant is generated via new large-volume spatial dimensions, while Standard Model states are localized to a 3-brane. Utilizing compact hyperbolic manifolds (CHM's) we show that the spectrum of Kaluza-Klein (KK) modes is radically altered. This allows an early universe cosmology with normal evolution up to substantial temperatures, and completely negates the constraints on M_* arising from astrophysics. Furthermore, an exponential hierarchy between the usual Planck scale and the true fundamental scale of physics can emerge with only order unity coefficients. The linear size of the internal space remains small. The proposal has striking testable signatures.