# Dynamical Compactification from de Sitter Space

 Title: Dynamical Compactification from de Sitter Space Author: Randall, Lisa; Johnson, Matthew C.; Carroll, Sean M. Note: Order does not necessarily reflect citation order of authors. Citation: Carroll, Sean M., Matthew C. Johnson, and Lisa Randall. 2009. Dynamical compactification from de Sitter space. Journal of High Energy Physics 11: 094. Full Text & Related Files: 0904.3115v2.pdf (829.4Kb; PDF) Abstract: We show that $$D$$-dimensional de Sitter space is unstable to the nucleation of non-singular geometries containing spacetime regions with different numbers of macroscopic dimensions, leading to a dynamical mechanism of compactification. These and other solutions to Einstein gravity with flux and a cosmological constant are constructed by performing a dimensional reduction under the assumption of $$q$$-dimensional spherical symmetry in the full $$D$$-dimensional geometry. In addition to the familiar black holes, black branes, and compactification solutions we identify a number of new geometries, some of which are completely non-singular. The dynamical compactification mechanism populates lower-dimensional vacua very differently from false vacuum eternal inflation, which occurs entirely within the context of four-dimensions. We outline the phenomenology of the nucleation rates, finding that the dimensionality of the vacuum plays a key role and that among vacua of the same dimensionality, the rate is highest for smaller values of the cosmological constant. We consider the cosmological constant problem and propose a novel model of slow-roll inflation that is triggered by the compactification process. Published Version: doi:10.1088/1126-6708/2009/11/094 Other Sources: http://arxiv.org/abs/0904.3115 Terms of Use: This article is made available under the terms and conditions applicable to Open Access Policy Articles, as set forth at http://nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of-use#OAP Citable link to this page: http://nrs.harvard.edu/urn-3:HUL.InstRepos:8052090 Downloads of this work: