ISSN:
1572-9532
Keywords:
Early universe
;
time–dependent Λ
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract We consider cosmology in the framework of a ‘material reference system’ of $$\mathcal{D}$$ particles, including the effects of quantum recoil induced by closed-string probe particles. We find a time-dependent contribution to the cosmological vacuum energy, which relaxes to zero as ∼1/t 2 for large times t. If this energy density is dominant, the Universe expands with a scale factor R(t)∼t 2. We show that this possibility is compatible with recent observational constraints from high–redshift supernovae, and may also respect other phenomenological bounds on time variation in the vacuum energy imposed by early cosmology.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1001993226227
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