Cosmic Acceleration and Modified Gravitational Models ∗
نویسنده
چکیده
There is now overwhelming observational evidence that our Universe is accelerating in its expansion. I discuss how modified gravitational models can provide an explanation for this observed late-time cosmic acceleration. We consider specific lowcurvature corrections to the Einstein-Hilbert action. Many of these models generically contain unstable de Sitter solutions and, depending on the parameters of the theory, late-time accelerating attractor solutions. Based on talks given at MRST-04, PASCOS-04 and COSMO-04. [email protected] Cosmic Acceleration and Modified Gravitational Models 2
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