Optimal parameterizations for observational constraints on thawing dark energy

Abstract

Time-varying dark energy is often modeled in observational analyses through generic parameterizations of its equation of state $w(z)$, which typically use two free parameters $\{w_0,w_a\}$ to span a broad range of behaviors as a function of redshift. However, this broad range of behaviors can only approximately capture the dynamics of any given microphysical theory of dark energy. A complementary approach is to use targeted parameterizations designed to model specific classes of dynamical dark energy with greater precision. Focusing on the class of thawing dark energy, we quantify and compare the precision with which nineteen generic and targeted parameterizations can capture the dynamics of physically motivated thawing quintessence theories. We find that a targeted parameterization derived from a Padé expansion of $w$ is the most reliable of these, producing accurate reconstructions of $w(z)$, the expansion history $H(z)$, and cosmological parameters such as $H_0$ and ${\Omega }_m$ for a broad range of microphysical theories.

22 pages, 3 figures, matches version in JCAP

References in corpus (58)

• Cosmological parameters from CMB and other data: a Monte-Carlo approach
• Cosmology and the Fate of Dilatation Symmetry
• Exploring the Expansion History of the Universe
• A Model of Holographic Dark Energy
• The Pantheon+ Analysis: Cosmological Constraints
• Planck 2018 results. V. CMB power spectra and likelihoods
• DESI 2024 VI: Cosmological Constraints from the Measurements of Baryon Acoustic Oscillations
• Cobaya: Code for Bayesian Analysis of hierarchical physical models
• Quintessence: A Review
• Efficient sampling of fast and slow cosmological parameters
• DESI DR2 Results II: Measurements of Baryon Acoustic Oscillations and Cosmological Constraints
• CMB power spectrum parameter degeneracies in the era of precision cosmology
• The Atacama Cosmology Telescope: DR6 Gravitational Lensing Map and Cosmological Parameters
• Trans-Planckian Censorship and the Swampland
• The Atacama Cosmology Telescope: A Measurement of the DR6 CMB Lensing Power Spectrum and its Implications for Structure Growth
• A parametric model for dark energy
• Accurate halo-model matter power spectra with dark energy, massive neutrinos and modified gravitational forces
• Crossing the Phantom Divide with Parameterized Post-Friedmann Dark Energy
• The landscape, the swampland and the era of precision cosmology
• The Dynamics of Quintessence, The Quintessence of Dynamics
• High-redshift cosmography: auxiliary variables versus Padé polynomials
• The Paths of Quintessence
• Quantum Cosmological Perturbations: Predictions and Observations
• Robust Preference for Dynamical Dark Energy in DESI BAO and SN Measurements
• A new kind of cyclic universe
• Assessing observational constraints on dark energy
• Scant evidence for thawing quintessence
• Observational Constraints on Quintessence: Thawing, Tracker, and Scaling models
• Hilltop Quintessence
• DESI DR2 Results I: Baryon Acoustic Oscillations from the Lyman Alpha Forest
• Underdetermination of dark energy
• Hints of Nonminimally Coupled Gravity in DESI 2024 Baryon Acoustic Oscillation Measurements
• Matching current observational constraints with nonminimally coupled dark energy
• A Comparison of Thawing and Freezing Dark Energy Parametrizations
• Can dark energy be dynamical?
• Robustness of dark energy phenomenology across different parameterizations
• Swampland Conjectures and Late-Time Cosmology
• Calibrating Dark Energy
• Of pNGB QuiNtessence
• Taking Bigger Metropolis Steps by Dragging Fast Variables
• Observational constraints on thawing quintessence models
• Quintessence's Last Stand?
• Confronting pNGB quintessence with data
• Observational Constraints on Axion(s) Dark Energy with a Cosmological Constant
• Cosmological tests of quintessence in quantum gravity
• Rapidly Descending Dark Energy and the End of Cosmic Expansion
• Field Flows of Dark Energy
• Testing an oscillatory behavior of dark energy
• Exploring Parameter Constraints on Quintessential Dark Energy: The Exponential Model
• To curve, or not to curve: Is curvature-assisted quintessence observationally viable?
• Observational Constraints on Axions as Quintessence in String Theory
• The Dark Energy Cosmic Clock: A New Way to Parametrise the Equation of State
• Generalizing thawing dark energy models: the standard vis-à-vis model independent diagnostics
• General parametrization for energy density of quintessence field
• New simple and accurate quintessence approximations
• Distinguishing freezing and thawing dark energy models through measurements of the fine-structure constant
• Trans-Planckian censorship constraints on properties and cosmological applications of axion-like fields
• Observational constraints on thawing quintessence scalar field model

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• Improved null tests of $\Lambda$CDM and FLRW in light of DESI DR2
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• Metastability in Emergent Dark Energy: A New Framework Confronting Cosmological Observations
• Model-Independent Dark Energy Measurements from DESI DR2 and Planck 2015 Data
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• Realizing the phantom-divide crossing with vector and scalar fields
• Thawing Quintessence: Priors, evidence, and likely trajectories
• Thermodynamic reconstruction in observationally constrained dynamical dark energy models
• Is the $\Lambda$CDM Model in Crisis?
• Sound Mode and Scale-Dependent Growth in Two-Fluid Dynamical Dark Energy
• Breaking Free from the Swampland of Impossible Universes through the DESI Portal