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Cosmology

Cosmology

Quintessence

01 Nov 2000

Cosmologists have proposed that a mysterious substance called quintessence can explain why our universe is accelerating. But what is it made of, ask Robert R Caldwell and Paul J Steinhardt

Data from observations and experiments – such as measurements of supernovae (left), the cosmic mic

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Robert R Caldwell is in the Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Laboratory, Hanover, New Hampshire 03755-3528, USA ( www.dartmouth.edu/artsci/physics/faculty/Caldwell.html). Paul J Steinhardt is in the Department of Physics, Princeton University, Princeton, New Jersey 08544, USA (feynman.princeton.edu/~steinh/)
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