The cosmological constant from the zero point energy of compact dimensions

TL;DR

This paper proposes that the quantum zero point energy of compact extra dimensions can account for the observed cosmological constant, linking fundamental physics with cosmological observations.

Contribution

It introduces a model where zero point energy from compact dimensions explains the cosmological constant, with specific size estimates for the extra dimensions.

Findings

Compact dimensions of order 10^{-2} cm produce the observed cosmological constant.

Zero point energy in extra dimensions can generate a homogeneous, isotropic energy density.

The model aligns quantum field effects with cosmological observations.

Abstract

We consider extra compact dimensions as the origin of a cosmological universal energy density in the regular dimensions, with only graviton fields propagating in the compact space dimensions. The quantum zero point energy originating from the finite size boundary condition in the compact dimensions can produce a constant energy density in regular $3$ space which is homogeneous and isotropic. It then makes a natural identification with the cosmological constant in conformity with the Einstein equation. It turns out that for the emergent energy density to agree with the observed value of the cosmological constant, the size/radius of compact dimension is to be of order of $10^{-2}$ cm.