The accelerating universe as a research area investigates the observed late-time acceleration of cosmic expansion and its implications for fundamental physics and cosmology. It encompasses precise measurements of distance–redshift relations using Type Ia supernovae, baryon acoustic oscillations, and weak gravitational lensing, as well as constraints from cosmic microwave background anisotropies and large-scale structure growth. The field focuses on characterizing dark energy (e.g., cosmological constant, dynamical scalar fields, or modified gravity), determining its equation-of-state parameter and possible evolution, testing general relativity on cosmological scales, and developing theoretical frameworks and numerical simulations to reconcile observational data with models of cosmic expansion history.
The universe is approaching the midpoint of its 33-billion-year lifespan, a Cornell physicist calculates with new data from dark-energy observatories. After expanding to its peak size about 11 billion years from now, it will ...
Astronomy
Oct 1, 2025
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For decades, astronomers have believed that dark matter and dark energy make up most of the universe. However, a new study suggests they might not exist at all. Instead, what we perceive as dark matter and dark energy could ...
Astronomy
Oct 1, 2025
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Science is a story of coming up with theories then doing our best to disprove them. That is especially true for theories on a grand, cosmological scale, though disproving them can be particularly hard.
Astronomy
Sep 16, 2025
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Dark energy—the term used to describe whatever is causing the universe to expand at an increasing rate—is one of the universe's greatest mysteries. The most widely accepted theory currently suggests that dark energy is ...
Astronomy
Sep 15, 2025
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These are exciting times to explore the largest unanswered questions in physics thanks to high-tech experiments and very precise data. That's particularly true of dark energy, the name given to the mysterious driver of the ...
Astronomy
Aug 21, 2025
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For thousands of years, humanity viewed the skies as unchanging, except for a few "wandering stars" (that we now know are planets). As we improved our ability to perceive the cosmos with light-gathering telescopes and electronic ...
Astronomy
Aug 13, 2025
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It took about 50 exploding stars to upend cosmology. Researchers mapped and measured light from Type Ia supernovae, the dramatic explosion of a particular kind of white dwarf. In 1998, they announced their surprising results: ...
Astronomy
Jul 21, 2025
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For generations, humans have gazed at the stars and wondered about the ultimate fate of the universe. Will it expand forever into the cold emptiness, or meet a more dramatic end?
Astronomy
Jul 6, 2025
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The birth, growth and future of our universe are eternally fascinating.
Astronomy
Jun 30, 2025
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String theory has long been touted as physicists' best candidate for describing the fundamental nature of the universe, with elementary particles and forces described as vibrations of tiny threads of energy. But in the early ...
General Physics
Jun 9, 2025
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