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Cosmological Imprint of an Energy Component with General Equation of State

R. R. Caldwell·Rahul Dave·Paul J. Steinhardt
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Abstract

We examine the possibility that a significant component of the energy density of the universe has an equation-of-state different from that of matter, radiation or cosmological constant ($Λ$). An example is a cosmic scalar field evolving in a potential, but our treatment is more general. Including this component alters cosmic evolution in a way that fits current observations well. Unlike $Λ$, it evolves dynamically and develops fluctuations, leaving a distinctive imprint on the microwave background anisotropy and mass power spectrum.

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R. R. Caldwell, Rahul Dave, Paul J. Steinhardt. 1998-02-06. Cosmological Imprint of an Energy Component with General Equation of State. https://doi.org/10.1103/physrevlett.80.1582

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