Probing the dynamical behavior of dark energy

Abstract

We investigate dynamical behavior of the equation of state of dark energy $w_{de}$ by employing the linear-spline method in the region of low redshifts from observational data (SnIa, BAO, CMB and 12 $H(z)$ data). The redshift is binned and $w_{de}$ is approximated by a linear expansion of redshift in each bin. We leave the divided points of redshift bins as free parameters of the model, the best-fitted values of divided points will represent the turning positions of $w_{de}$ where $w_{de}$ changes its evolving direction significantly (if there exist such turnings in our considered region). These turning points are natural divided points of redshift bins, and $w_{de}$ between two nearby divided points can be well approximated by a linear expansion of redshift. We find two turning points of $w_{de}$ in $z\in (0,1.8)$ and one turning point in $z\in (0,0.9)$, and $w_{de}(z)$ could be oscillating around $w=-1$. Moreover, we find that there is a $2\sigma$ deviation of $w_{de}$ from -1 around $z=0.9$ in both correlated and uncorrelated estimates.

Accepted by JCAP; 16 pages, 3 figures

References in corpus (19)

• Seven-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• Dynamics of dark energy
• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• A Dark Energy Model Characterized by the Age of the Universe
• A New Model of Agegraphic Dark Energy
• CfA3: 185 Type Ia Supernova Light Curves from the CfA
• A Holographic Dark Energy Model from Ricci Scalar Curvature
• Observational constraints on the dark energy and dark matter mutual coupling
• The imprint of the interaction between dark sectors in large scale cosmic microwave background anisotropies
• On the Dark Sector Interactions
• Oscillating universe with quintom matter
• Fitting the Constitution SNIa Data with Redshift Binned Parameterization Method
• Narrowing Constraints with Type Ia Supernovae: Converging on a Cosmological Constant
• Comparison of Recent SnIa datasets
• Distance Measurements from Supernovae and Dark Energy Constraints
• Deviation from the Cosmological Constant or Systematic Errors?
• High-resolution temporal constraints on the dynamics of dark energy
• Crossing the phantom divide
• Detecting Features in the Dark Energy Equation of State: A Wavelet Approach

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