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I Got Your Neutrinos Right Here
The oldest of the subatomic particles called neutrinos might
each encompass a space larger than thousands of galaxies, simulations suggest.
We think of fundamental particles as being very small, but “relic” neutrinos left over from the big bang could be big. Really big. The quantum wave describing one could be billions of light-years across, a good fraction of the observable universe. Such a large wave raises questions about how a quantum particle interacts with gravity at the scale of galaxies and galaxy clusters -- questions that remain unresolved.
University of California researchers George Fuller and Chad Kishimoto were checking whether a theoretical upper limit could be placed on neutrino masses based on galaxy observations when they realized that the wave functions describing
relic neutrinos might extend billions of light years. Half of a neutrino’s wave function could, for instance, be in our galaxy while the other half would be out at the edge of the observable universe.
(from 2009 article)
Fresh neutrinos like CERN recently clocked exceeding lightspeed are exempt from such speculation.
Physics - Ginormous Neutrino
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