Abstract
The physical Hamiltonian of a gravity-matter system depends on the choice of time, with the vacuum naturally identified as its ground state. We study the expanding Universe with scalar field in the volume time gauge. We show that the vacuum energy density computed from the resulting Hamiltonian is a nonlinear function of the cosmological constant and time. This result provides a new perspective on the relation between time, the cosmological constant, and vacuum energy.
- Received 4 September 2015
DOI:https://doi.org/10.1103/PhysRevLett.116.061302
© 2016 American Physical Society
Physics Subject Headings (PhySH)
Gravitation, Cosmology & AstrophysicsParticles & Fields