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arXiv · 1004.3888

Stability of multi-field cosmological solutions in the presence of a fluid

Jonathan Frazer·Andrew R Liddle
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Abstract

We explore the stability properties of multi-field solutions in the presence of a perfect fluid, as appropriate to assisted quintessence scenarios. We show that the stability condition for multiple fields $ϕ_i$ in identical potentials $V_i$ is simply $d^2V_i/d ϕ_i^2 > 0$, exactly as in the absence of a fluid. A possible new instability associated with the fluid is shown not to arise in situations of cosmological interest.

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Jonathan Frazer, Andrew R Liddle. 2010-07-27. Stability of multi-field cosmological solutions in the presence of a fluid. https://doi.org/10.1103/physrevd.82.043516

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