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arXiv · 2201.07596

Cosmological global dynamical systems analysis

Artur Alho·Woei Chet Lim·Claes Uggla
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Abstract

We consider a dynamical systems formulation for models with an exponential scalar field and matter with a linear equation of state in a spatially flat and isotropic spacetime. In contrast to earlier work, which only considered linear hyperbolic fixed point analysis, we do a center manifold analysis of the non-hyperbolic fixed points associated with bifurcations. More importantly though, we construct monotonic functions and a Dulac function. Together with the complete local fixed point analysis this leads to proofs that describe the entire global dynamics of these models, thereby complementing previous local results in the literature.

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Artur Alho, Woei Chet Lim, Claes Uggla. 2022-01-19. Cosmological global dynamical systems analysis. https://doi.org/10.1088/1361-6382%2Fac7769

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