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Opportunities for future supernova studies of cosmic acceleration
1Department of Physics, University of California at Davis, California 95616, USA.
Physical Review Letters
|April 6, 2001
Summary
Future supernova data from the SNAP satellite can help distinguish between dark energy theories. Analyzing the pressure-to-density ratio (w) and its change over time (dw/dz) improves model discrimination, especially with better mass density measurements.
Area of Science:
- Cosmology
- Astrophysics
- Particle Physics
Background:
- The accelerating expansion of the Universe is a key area of modern cosmology.
- Dark energy theories attempt to explain this acceleration.
- Distinguishing between these theories requires precise observational data.
Purpose of the Study:
- To assess the capability of future supernova surveys, like those from the proposed SNAP satellite, in differentiating various dark energy models.
- To determine which cosmological parameters are most crucial for model discrimination.
Main Methods:
- Utilizing simulated supernova data, specifically focusing on luminosity distance measurements.
- Employing fitting functions to analyze the data and constrain cosmological parameters.
- Investigating the diagnostic power of the equation of state parameter (w) and its evolution (dw/dz).
Main Results:
- Many dark energy models can be distinguished by fitting the effective pressure-to-density ratio (w).
- Improved discrimination is achieved by also fitting the effective slope of w (dw/dz), provided current mass density (Omega(m)) is better constrained.
- Luminosity distance data from supernova searches are a viable tool for these investigations.
Conclusions:
- Future supernova data, particularly from missions like SNAP, will be instrumental in testing dark energy theories.
- Precise measurements of w and its evolution are critical for understanding the nature of dark energy.
- Enhanced constraints on Omega(m) will further boost the power of supernova surveys to probe cosmological models.
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