Abstract
We consider a possibility that the cosmological constant may not be a constant, but a free thermodynamical variable. To this end we construct a microscopic model of a spacelike two-sphere just inside of the cosmological horizon of the de Sitter spacetime. In our model the spacelike two-sphere in question is assumed to consist of discrete constituents, each of them contributing to the two-sphere an area, which is an integer times a constant. Using our model we obtain a thermodynamical equation of state for the cosmological constant. Our equation of state implies that the cosmological constant has a certain positive lower bound, which depends on the number of the constituents of the two-sphere.
- Received 15 January 2013
DOI:https://doi.org/10.1103/PhysRevD.87.104040
© 2013 American Physical Society