Neutrinos left over from the big bang may stretch billions of light years across the universe (Image: Henry / Flickr)

TALK about misnomers. It seems the particles that Enrico Fermi dubbed neutrinos, meaning “little neutral ones”, might stretch across billions of light years.

The big bang produced huge numbers of “relic” neutrinos, which are quantum-mechanical superpositions of three different mass-energy states. In the early universe, all of these states would have moved at close to the speed of light. But according to calculations by George Fuller and Chad Kishimoto of the University of California, San Diego, as the universe expanded, the most massive of these states slowed down in the relic neutrinos, …