[Paper Review] The Holographic dark energy revisited

Yungui Gong, Bin Wang+1 more|arXiv (Cornell University)|Dec 19, 2004

Cosmology and Gravitation Theories3 citations

TL;DR

This paper revisits the holographic dark energy model by incorporating spatial curvature, refining model parameters to show the universe is likely closed. Using supernova data alone, it finds the closed universe is favored, and combining with WMAP data yields a reasonable spatial curvature value, indicating the holographic dark energy model does not behave as phantom dark energy.

ABSTRACT

We have reexamined the holographic dark energy model by considering the spatial curvature. We have refined the model parameter and observed that the holographic dark energy model does not behave as phantom. Applying the holographic dark energy model and comparing to the supernova observation alone, we found that the closed universe is favored. Combining with the WMAP data, we obtained the reasonable value of the spatial curvature of our universe.

Motivation & Objective

• To re-express the holographic dark energy model by including spatial curvature for improved cosmological consistency.
• To reassess whether the holographic dark energy model exhibits phantom-like behavior, given its implications for cosmic evolution.
• To constrain the spatial curvature of the universe using observational data, particularly supernovae and WMAP results.
• To refine model parameters in light of updated cosmological observations, ensuring compatibility with current data.

Proposed method

• Incorporated spatial curvature into the holographic dark energy model, modifying the standard energy density relation.
• Used the holographic principle to relate the dark energy density to the size of the future event horizon.
• Applied supernova Type Ia observations to constrain the model parameters and test the viability of the closed universe scenario.
• Combined supernova data with WMAP cosmic microwave background data to improve constraints on spatial curvature.
• Performed statistical analysis to compare model predictions with observational data, focusing on curvature and equation of state.

Experimental results

Research questions

• RQ1 Does the inclusion of spatial curvature alter the behavior of the holographic dark energy model, particularly in terms of the equation of state?
• RQ2 Is the holographic dark energy model consistent with a closed universe when constrained by supernova data alone?
• RQ3 What is the constrained value of spatial curvature when combining supernova and WMAP data in the holographic dark energy framework?
• RQ4 Does the holographic dark energy model exhibit phantom-like behavior, as indicated by w < -1?

Key findings

• The holographic dark energy model does not behave as phantom dark energy, as the equation of state remains above -1.
• Supernova data alone favor a closed universe, indicating negative spatial curvature.
• Combining supernova data with WMAP data yields a reasonable and consistent value for the spatial curvature of the universe.
• The refined model parameters show improved agreement with current cosmological observations, particularly in the context of curvature constraints.