Vacuum Structure and Dark Energy

Abstract

We consider that the universe is trapped in an excited vacuum state and the resulting excitation energy provides the observed dark energy. We explore the conditions under which this situation can arise from physics already known. Considering the example of how macroscopic QED fields alter the vacuum structure, we find that the energy scale 1 meV --- 1 eV is particularly interesting. We discuss how dark energy of this form is accessible to laboratory experiments.

Comments: 5 pages, 2 figures; recognized for Honorable Mention in 2010 Gravity Research Foundation Awards for Essays on Gravitation, in press with Int. J. Mod. Phys. D