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Dark energy two decades after: observables, probes, consistency tests
Dragan Huterer1, Daniel L Shafer2
1Department of Physics, University of Michigan, 450 Church Street, Ann Arbor, MI 48109, United States of America.
Reports on Progress in Physics. Physical Society (Great Britain)
|November 10, 2017
Summary
The universe is accelerating due to dark energy, a dominant cosmic component. This review explores dark energy
Area of Science:
- Cosmology
- Astrophysics
- Fundamental Physics
Background:
- The discovery of the accelerating universe in the late 1990s revealed a dominant energy component.
- Strong evidence for dark energy has accumulated from precise measurements of cosmic expansion and structure growth.
Purpose of the Study:
- To review the historical developments leading to the discovery of dark energy.
- To discuss parametric descriptions and cosmological tests for understanding dark energy's nature.
- To summarize current research and prospects for probing dark energy properties.
Main Methods:
- Review of historical discoveries and theoretical frameworks.
- Analysis of parametric models and cosmological tests.
- Examination of various cosmological probes (e.g., supernovae, cosmic microwave background, large-scale structure).
Main Results:
- Dark energy is the leading candidate for the cause of cosmic acceleration.
- Multiple cosmological probes provide consistent, albeit still imprecise, measurements of dark energy properties.
- Significant challenges remain in elucidating the physical nature of dark energy.
Conclusions:
- The accelerating universe and dark energy are well-established phenomena in modern cosmology.
- Ongoing and future cosmological surveys aim to precisely measure dark energy's equation of state.
- Understanding dark energy's physical origin is a primary goal for fundamental physics.
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