Vacuum energy and the cosmological constant

Abstract

The accelerating expansion of the Universe points to a small positive value for the cosmological constant or vacuum energy density. We discuss recent ideas that the cosmological constant plus LHC results might hint at critical phenomena near the Planck scale.

Comments: 15 pages, Contributed paper to the Special Issue "Fundamental Constants in Physics and Their Time Variation" (Modern Physics Letters A, Guest Editor Joan Solà)