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Cosmological models with variable gravitational and cosmological “constants”. (English) Zbl 0953.83074
Summary: We consider the Einstein field equations with perfect fluid source and variable Λ and G for the Robertson-Walker metric. When conservation of energy-momentum is postulated and the deceleration parameter is assumed constant, we find the perfect gas equation of state models in the Euclidean and non-Euclidean cases. The resulting models offer an alternative to the inflationary scenario; they also explain the huge value of the cosmological term in the early universe.

83F05Relativistic cosmology
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