Quintessence Cosmologies with a Double Exponential Potential
نویسنده
چکیده
We use phase space methods to investigate closed, flat, and open FriedmannRobertson-Walker cosmologies with a scalar potential given by the sum of two exponential terms. The form of the potential is motivated by the dimensional reduction of M-theory with non-trivial four-form flux on a maximally symmetric internal space. To describe the asymptotic features of run-away solutions we introduce the concept of a ‘quasi fixed point.’ We give the complete classification of solutions according to their late-time behavior (accelerating, decelerating, crunch) and the number of periods of acceleration. Work supported by the ‘Schwerpunktprogramm Stringtheorie’ of the DFG.
منابع مشابه
Phase Space Analysis of Quintessence Cosmologies with a Double Exponential Potential
We use phase space methods to investigate closed, flat, and open FriedmannRobertson-Walker cosmologies with a scalar potential given by the sum of two exponential terms. The form of the potential is motivated by the dimensional reduction of M-theory with non-trivial four-form flux on a maximally symmetric internal space. To describe the asymptotic features of run-away solutions we introduce the...
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