Intermediate inflation and the slow-roll approximation
نویسنده
چکیده
It is shown that spatially homogeneous solutions of the Einstein equations coupled to a nonlinear scalar field and other matter exhibit accelerated expansion at late times for a wide variety of potentials V . These potentials are strictly positive but tend to zero at infinity. They satisfy restrictions on V ′/V and V ′′/V ′ related to the slow-roll approximation. These results generalize Wald’s theorem for spacetimes with positive cosmological constant to those with accelerated expansion driven by potentials belonging to a large class.
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