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Dark energy
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Mysterious cause of accelerating expansion.
About 68% of the universe, with negative pressure causing accelerated expansion, discovered via distant supernovae in 1998 (Nobel 2011). The cosmological constant is the simplest model.
Its density is about 6×10⁻²⁷ kg/m³.
Different from dark matter.
In more detail
Dark energy is the mysterious component that drives the accelerating expansion of the universe, making up about 68 percent of its energy content. Its nature is unknown.
Real-world uses
- Dark energy determines the long-term fate of the universe.
- Cosmological surveys measure its effect on expansion.
- Cosmologists use the accelerating expansion of the universe, discovered from supernovae, as evidence for dark energy.
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Frequently asked questions
What is the leading explanation?
The cosmological constant, a constant energy density of empty space.
Will dark energy ever end?
Current models predict continued acceleration, but this may change with new data.
Is dark energy the same as dark matter?
No. Dark energy drives the expansion, while dark matter clumps under gravity; they are different and unrelated components.
Related topics in Particle Physics & Cosmology
Big Bang nucleosynthesis · Inflation · Dark matter · Critical density · Fate of the universe · Exoplanets