Exact general solutions for cosmological scalar field evolution in a background-dominated expansion
نویسندگان
چکیده
We derive exact general solutions (as opposed to attractor particular solutions) and corresponding first integrals for the evolution of a scalar field $\phi$ in universe dominated by background fluid with equation state parameter $w_B$. In addition previously-examined linear [$V(\phi) = V_0 \phi$] quadratic \phi^2$] potentials, we show that exist power law potential $V(\phi) \phi^n$ $n 4(1+w_B)/(1-w_B) + 2$ 2(1+w_B)/(1-w_B)$. These correspond potentials \phi^6$ \phi^2$ matter domination \phi^{10}$ \phi^4$ radiation domination. The $\phi^6$ $\phi^{10}$ can yield either oscillatory or non-oscillatory evolution, use determine how initial conditions map onto each form evolution. exponential yields an solution stiff/kination ($w_B 1$) background. this analytic expression parameter, $w_\phi$, case.
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ژورنال
عنوان ژورنال: Physical review
سال: 2022
ISSN: ['0556-2813', '1538-4497', '1089-490X']
DOI: https://doi.org/10.1103/physrevd.105.103502