Multiverse Model: External Universe(s) as Source of Dark Energy

Abstract

The Lambda Cold Dark Matter (ΛCDM) model is currently the best model to describe the development of the Universe from the Big Bang to the present time. It is composed of six parameters, two of them, Dark Energy (DE) and CDM, with unknown physical explanations. DE, leading to accelerated expansion of the Universe, is considered a scalar field characterized by exerting its force by repulsive gravity. We examined whether DE can be explained as the warping of spacetime in our Universe by external universes as components of a Multiverse or, in other words, as the gravitational pull exerted by other universes. The acceleration, the resultant kinetic energy, Ekin, and the cosmological constant, Λ, were calculated for one to four external universes. The acceleration is approx. 10-11 m/s2, which is in agreement with observations. Its value is dependent upon the numbers and relative positions of external universes. DE density is approx. 10-29 kg/m3 and Λ is in the range of 10-38 s-2 and 10-55 m-2, respectively. Warping of spacetime by external universes as a physical explanation for DE seems feasible and warrants further considerations.