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Growth rate in the dynamical dark energy models
Olga Avsajanishvili1, Natalia A Arkhipova2, Lado Samushia3
1Abastumani Astrophysical Observatory, Ilia State University, 3-5 Cholokashvili Ave., Tbilisi, 0194 Georgia.
The European Physical Journal. C, Particles and Fields
|June 5, 2015
Summary
This study explores scalar field dark energy models as an alternative to the cosmological constant. Using cosmic expansion and growth data, we constrain the scalar field potential parameter.
Area of Science:
- Cosmology
- Theoretical Physics
- Astrophysics
Background:
- The standard cosmological model relies on a time-independent cosmological constant for dark energy.
- Scalar field dark energy models offer a dynamic alternative, with a slowly rolling scalar field.
Purpose of the Study:
- Investigate the Ratra-Peebles scalar field model with a specific self-interaction potential.
- Simultaneously analyze the evolution of cosmic expansion and structure growth within this model.
- Constrain the model's parameter describing the scalar field potential's steepness using observational data.
Main Methods:
- Utilized recent measurements of the linear growth rate of cosmic structures.
- Incorporated baryon acoustic oscillation peak positions as cosmological probes.
- Applied these datasets to constrain the scalar field potential parameter, often denoted by ξ (xi).
Main Results:
- The study successfully constrained the parameter ξ, which quantifies the steepness of the scalar field potential.
- This constraint provides valuable information about the dynamics of scalar field dark energy.
- The findings contribute to differentiating between various dark energy models.
Conclusions:
- Scalar field dark energy models, particularly the Ratra-Peebles model, remain viable alternatives to the cosmological constant.
- Observational data on cosmic expansion and growth are effective in probing dark energy dynamics.
- Further research can refine these constraints and explore other scalar field potentials.
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