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Article: Ripples in the sands of time; The cosmic neutrino background.
- Article from:
- The Economist (US)
- Article date:
- June 25, 2005
CopyrightCOPYRIGHT 2005 Economist Newspaper Ltd. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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Cosmologists find hints of an elusive relic of the universe's beginning
CONTRARY to popular opinion, empty space is not actually empty--it positively buzzes with subatomic particles. Many of these are photons, the particles of which electromagnetic radiation (light, microwaves, radio waves and so on) is composed. And most of those photons are part of a relic known as the cosmic microwave background (CMB).
The CMB is made up of photons that began their journey 300,000 years after the Big Bang that marks the beginning of the universe. By analysing ripples imprinted on the CMB, cosmologists can see a picture of the universe as it then was. This has allowed ...