The cosmological constant and oscillating metrics
نویسنده
چکیده
The presence of a cosmological constant, Λ, in an action with higher powers of the curvature can produce rapidly oscillating metrics. We develop a perturbative approach for generating periodic solutions to the non-linear field equations for such actions based on a small amplitude expansion. We find that these oscillations have an amplitude proportional to √ Λ and a frequency of order the Planck mass. In a 4+1-dimensional scenario, a family of metrics exists that are periodic in the extra dimension and are parameterized by an effective four-dimensional cosmological constant which drives a rapid oscillation.
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تاریخ انتشار 2002