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| Cosmic Microwave Background mapping |
The theory is called Big Bang nucleosynthesis and describes a stage early in the universe's evolution when, at temperatures of thousands of degrees, protons and neutrons began to assemble into atomic nuclei and form the first light elements: deuterium, along with isotopes of helium and lithium. As temperatures dropped, nucleosynthesis drew to a close, and eventually electrons began to add themselves to the nuclei during a period called recombination. At this time, photons stopped scattering off charged particles and the universe became transparent.
Sikivie and colleagues point out that axions can form a Bose–Einstein condensate (BEC). Such condensates contain particles that have all fallen into their lowest energy state, and are best known to occur in low-density gases at temperatures close to absolute zero. But since the critical temperature for transition to a BEC depends on density, say the Florida researchers, particles can form BECs at higher temperatures as long as they are dense enough. Even in the primordial heat of the Big Bang, the researchers say, axions would easily be dense enough to form a BEC.
Sikivie and colleagues point out that axions can form a Bose–Einstein condensate (BEC). Such condensates contain particles that have all fallen into their lowest energy state, and are best known to occur in low-density gases at temperatures close to absolute zero. But since the critical temperature for transition to a BEC depends on density, say the Florida researchers, particles can form BECs at higher temperatures as long as they are dense enough. Even in the primordial heat of the Big Bang, the researchers say, axions would easily be dense enough to form a BEC.
All well for the universe: what about my laptop battery?
Physics World: Axions could solve lithium problem
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