Is There a Cosmological Constant?
نویسندگان
چکیده
منابع مشابه
The Cosmological Constant Is Back
SUMMARY A diverse set of observations now compellingly suggest that Universe possesses a nonzero cosmological constant. In the context of quantum-field theory a cosmological constant corresponds to the energy density of the vacuum, and the wanted value for the cosmological constant corresponds to a very tiny vacuum energy density. We discuss future observational tests for a cosmological constan...
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We consider a recent proposal to solve the cosmological constant problem within the context of brane world scenarios with infinite volume extra dimensions. In such theories bulk can be supersymmetric even if brane supersymmetry is completely broken. The bulk cosmological constant can therefore naturally be zero. Since the volume of the extra dimensions is infinite, it might appear that at large...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 1996
ISSN: 0004-637X,1538-4357
DOI: 10.1086/177538