Using the Dilaton Potential to Obtain String Cosmology Solutions
نویسنده
چکیده
We examine the string cosmology equations with a dilaton potential, contrasting the requirements that the equations and their solutions have the desired a → 1/a pre-big bang symmetry, and give a generic algorithm for obtaining solutions with desired evolutionary properties. This enables us to find pre-big bang type solutions that are regular at t = 0, and with suitable dilaton behaviour. However to avoid fine tuning of initial data, an ‘exotic’ equation of state is needed that relates the fluid properties to the dilaton field. We discuss why such an equation of state should be required for reliable dilaton behaviour at late times.
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تاریخ انتشار 1999