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Dark matter
Since more than 20 years, a strange puzzle gives headaches to astrophysicists. Measurements of the orbital velocity of stars in many galaxies give unexpected results. The outer stars of galaxies are orbiting more rapidly than expected. Gravitation has been doubted and an hypothetical fifth force was invented... but nothing was able to give a simple explanation to those too high velocities. An other explanation is that some dark matter, invisible, is orbiting around and inside the galaxies, only detectable through its gravitational effects. If neutrinos were massive, they would be good candidates to this dark matter, since the theory says that they must be numerous in the universe: 330 neutrinos per cm3. A good candidate, but with the condition that its mass is neither too small nor to high.
The missing solar neutrinos
Since 1975, and especially since 1995, physicists know with assurance that the neutrinos coming from our sun are largely less than predicted. The theory, which elsewhere describes with an accurate precision how the sun lives, predicts about 64 billions of neutrinos per second and cm2, received on earth. Detectors like GALLEX or SAGE observe not more than 40 billions of neutrinos per second and cm2. Where are the missing neutrinos?...Either the model describing the sun, so remarkable, is erroneous, either something makes the neutrinos impossible to arrive on the earth of impossible to detect. If the neutrinos have a mass, then they could oscillate and those oscillations could explain the missing solar neutrinos.
Didier Verkindt