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arXiv · 2201.08841

Cosmological dynamics of multifield dark energy

Johannes R. Eskilt·Yashar Akrami·Adam R. Solomon·Valeri Vardanyan
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Abstract

We numerically and analytically explore the background cosmological dynamics of multifield dark energy with highly nongeodesic or "spinning" field-space trajectories. These extensions of standard single-field quintessence possess appealing theoretical features and observable differences from the cosmological standard model. At the level of the cosmological background, we perform a phase-space analysis and identify approximate attractors with late-time acceleration for a wide range of initial conditions. Focusing on two classes of field-space geometry, we derive bounds on parameter space by demanding viable late-time acceleration and the absence of gradient instabilities, as well as from the de Sitter swampland conjecture.

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Johannes R. Eskilt, Yashar Akrami, Adam R. Solomon, Valeri Vardanyan. 2022-01-21. Cosmological dynamics of multifield dark energy. https://doi.org/10.1103/physrevd.106.023512

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