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NewsPapers
- Measuring the Universe (MSNBC News)
"How far away is that galaxy? The more precise your answer is, the more you can find out about mysterious dark energy. In the past, astronomers have used variable stars and a special kind of supernova to make their distance estimates - and now two new measuring sticks are being added to the toolbox." 06-09
- Dark Energy and Einstein's Constant (Scientific American)
"To the astronomers' amazement, they found that the universe is actually expanding faster now than it was billions of years ago." 02-11
- Supernovae Back Einstein's Constant (Scientific American)
"Now new observations from an international team of astronomers seem to show that dark energy is like the cosmological constant, unvarying throughout space and time. By measuring the distances to 71 far-off supernovae, the scientists were able to ascertain with a high degree of confidence that the effect dark energy exerts on supernovae light does not vary with distance. The researchers also plugged this data into a so-called equation of state, which measures the relationship between pressure and density, and found that dark energy must be less than -0.85--awfully close to Einstein's cosmological constant at -1. 'Our observation is at odds with a number of theoretical ideas about the nature of dark energy that predict that it should change as the universe expands and, as far as we can see, it doesn't,' says team member Ray Carlberg of the University of Toronto." 02-11
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