Uncertainty principle limits on the cosmological constant

Abstract

The identification of the cosmological constant term with the energy density of the vacuum enables lower and upper limits to be placed on its value. The upper limit arises from the constraint that the total zero-point energy, which also gravitates, should not dominate cosmological dynamics, while the lower limit can result from the operational requirement that the vacuum-energy shifts over atomic or nuclear scales be at least measurable over Hubble time scales.