Cosmology in Brans-Dicke theory with a scalar potential
نویسنده
چکیده
We consider the general behaviour of cosmologies in Brans-Dicke theory where the dilaton is self-interacting via a potential V (Φ). We show that the general radiation universe is a two-dimensional dynamical system whereas the dust or false vacuum universe is threedimensional. This is in contrast to the non-interacting dilaton which has uniformly a two-dimensional phase space. We find the phase spaces in each case and the general behaviour of the cosmologies. November, 1996 ∗ On leave from: Departmento de F́ısica da Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre 687, 4150-Porto, Portugal
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