Manyfold Universe

TL;DR

This paper proposes a model where our universe is a folded brane within extra dimensions, explaining dark matter as matter on other folds, predicting observable gravitational wave signals, and offering new insights into supersymmetry breaking and cosmology.

Contribution

It introduces the Manyfold universe model, where dark matter and sterile neutrinos are explained through brane folding, providing novel mechanisms for dark matter, supersymmetry breaking, and structure formation.

Findings

Dark matter can be microphysically identical to ordinary matter.

Enhanced gravitational wave signals due to frequent gravitational collapse.

Model consistent with current observational constraints.

Abstract

We propose that our world is a brane folded many times inside the sub-millimeter extra dimensions. The folding produces many connected parallel branes or folds with identical microphysics - a Manyfold. Nearby matter on other folds can be detected gravitationally as dark matter since the light it emits takes a long time to reach us traveling around the fold. Hence dark matter is microphysically identical to ordinary matter; it can dissipate and clump possibly forming dark replicas of ordinary stars which are good MACHO candidates. Its dissipation may lead to far more frequent occurrence of gravitational collapse and consequently to a significant enhancement in gravitational wave signals detectable by LIGO and LISA. Sterile neutrinos find a natural home on the other folds. Since the folded brane is not a BPS state, it gives a new geometric means for supersymmetry breaking in our world. It may also offer novel approach for the resolution of the cosmological horizon problem, although it still requires additional dynamics to solve the flatness problem. Although there are constraints from BBN, structure formation, the enormity of galactic halos and the absence of stars and globular clusters with a discernible dark matter component, we show that the model is consistent with current observational limits. It presents us with a new dark matter particle and a new framework for the evolution of structure in our universe.