2 1 0 Ju l 2 00 1 Hamilton - Jacobi approach to pre - big bang cosmology and the problem of initial conditions
نویسنده
چکیده
The Hamilton-Jacobi equation for the string cosmology is solved using the gradient expansion method. The zeroth order solution is taken to be the standard pre-big bang model and the second order solution is found for the dilaton and the three-metric. It indicates that corrections generated by inhomogeneities of the seed metric are suppressed near the singularity and are growing towards the asymptotic past, but corrections generated by the dilaton inhomogeneities are growing near the singularity and are suppressed in the past. Possible influences of initial metric inhomogeneities on the pre-big bang superinflation are discussed.
منابع مشابه
2 6 O ct 1 99 9 Hamilton - Jacobi approach to pre - big bang cosmology and the problem of initial conditions
The Hamilton-Jacobi equation for the low energy string effective action is solved using the gradient expansion method. The field equations are also expanded by the number of spatial gradients and the second order solution is found for the three-metric. The second order solution allows us to study the influence of initial inhomogeneities to the duration of pre-big bang superinflation. We conclud...
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