Bounds on Vacuum Energy Densityin a General Cosmological Scenario
نویسنده
چکیده
General limits on the cosmological constant (or equivalently the vacuum energy density) are derived for an inflationary universe. This is accomplished under the general assumption of global hyperbolicity and without the use of any special properties like spherical symmetry or homogeneity ofthe underlying spacetime. A clear upper limit of 1/3 is obtained for the vacuum energy density parameterQ~, while the lower limit is found to depend on the age of the oldest object in the universe.
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