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The Limits of Quintessence

R. R. Caldwell·Eric V. Linder
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Abstract

We present evidence that the simplest particle-physics scalar-field models of dynamical dark energy can be separated into distinct behaviors based on the acceleration or deceleration of the field as it evolves down its potential towards a zero minimum. We show that these models occupy narrow regions in the phase-plane of w and w', the dark energy equation-of-state and its time-derivative in units of the Hubble time. Restricting an energy scale of the dark energy microphysics limits how closely a scalar field can resemble a cosmological constant. These results, indicating a desired measurement resolution of order σ(w')\approx (1+w), define firm targets for observational tests of the physics of dark energy.

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R. R. Caldwell, Eric V. Linder. 2005-05-24. The Limits of Quintessence. https://doi.org/10.1103/physrevlett.95.141301

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