Ghostbusting
expected interaction. This discrepancy was dubbed ‘ the solar neutrino problem ’ . Davis repeated his experiment thoroughly and yet consistently received the same result. His experiment was so accurate and his problem so well known that it led to many other physicists experimenting in his field. In 2002 Davis received a Nobel Prize for his work.
An insight into lepton trends
A solution to the solar neutrino problem that Davis had uncovered came from the idea that there were three different ‘ flavours ’ of neutrino, each with a different rest mass. They were named the electron neutrino ( V e ), the muon neutrino ( V μ ) and the tau neutrino ( V τ ). The mathematical solar model for neutrino production could therefore still be correct. However, it was proven that the Davis Experiment was only able to detect one flavour of neutrino: the electron neutrino, thus explaining the discrepancy between the observed and emitted neutrinos. The focus then moved to try to answer why only one flavour of neutr ino reached the earth’s surface. In the standard model of particle physics, particles are found to get more massive as the generation increases. 5 For example, the tau particle is more massive than the muon which is in turn more massive than the electron. Theoretical physicists predicted that the same would be the case when considering the masses of the three types of neutrino. However, in their mathematical models, all neutrino masses are considered to be zero, whereas experimentally it interacted via the Higgs field and so was thought to have a rest mass above zero. Furthermore, experimentalists were unable to precisely measure the mass of each neutrino flavour with any degree of accuracy. In fact, they found it almost impossible to distinguish the rest mas for each separate flavour.
Fig.4. Showing two flavour oscillation pathways
Fig.3. Flavour oscillation graph (simplified)
Because of this experimental inability to distinguish a rest mass, an interesting postulate was formed; the so- called ‘Leptonic Flavour Oscillation’ . Simply put, this meant that a single neutrino would ‘change’ predictably between each flavour as it aged. This postulate emerged from the idea that fundamental particles exist as probability waves, originally suggested by the famous Planck equation
5 ‘ Each group [in the standard model of physics] consists of six particles, which are related in pairs, or ‘generations’. The lightest and most stable particles make up the first generation, whereas the heavier and less - st able particles belong to the second and third generations’ – CERN.
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