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View Full Version : Studying Dark Energy in Early Universe



Fortunate
2007-Oct-11, 10:10 PM
Proposal to study dark energy up to z = 6 or even z = 15 via 21 cm line from clumps of neutral hydrogen.
http://www.physorg.com/printnews.php?newsid=111333429


Wyithe and Loeb showed that, in fact, upcoming observatories will be capable of detecting 21-cm signals from the distant, young universe, even after it gets mostly ionized. Moreover, while the signal strength decreases after re-ionization, the noise also decreases. In principle, the 21-cm signal from neutral hydrogen can be measured from the present epoch all the way up to a redshift of z=15, when the universe was only 200 million years old.

"There is no other viable technique to study dark energy at high redshifts," stated Loeb.