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R. N. Mohapatra
partner lepton τ . This property is used to detect which kind of neutrino
is present in a given reaction. In the standard model, each type of neutrino
remains strictly “monogamous” with its corresponding partner lepton. Only
later, with the discovery of neutrino oscilliations, did there appear to be some
cross generational connection “breaking the strict monogamy rule” but that
is new physics beyond the standard model, which we discuss later. A couple
of facts: the leptons, unlike the quarks, do not experience the strong force. A
second interesting fact is that the existence of the tau neutrino was just recently
confirmed in an experiment called DONUT based in Fermilab, Batavia, by
an international collaboration. Thus all the leptons have now been separately
discovered.
Each family now has two quarks and two leptons and this is displayed
in Fig. 10.1. There is no strict “monogamy” property among quarks in the
standard model, as shown by experiments. The quarks mix with each other.
Also we note that once the neutrinos are established to have mass (as we
see below), their monogamy property is spoiled. They will start mixing with
different charged leptons and will not remain monogamous as in the standard
model.
R. N. Mohapatra
partner lepton τ . This property is used to detect which kind of neutrino
is present in a given reaction. In the standard model, each type of neutrino
remains strictly “monogamous” with its corresponding partner lepton. Only
later, with the discovery of neutrino oscilliations, did there appear to be some
cross generational connection “breaking the strict monogamy rule” but that
is new physics beyond the standard model, which we discuss later. A couple
of facts: the leptons, unlike the quarks, do not experience the strong force. A
second interesting fact is that the existence of the tau neutrino was just recently
confirmed in an experiment called DONUT based in Fermilab, Batavia, by
an international collaboration. Thus all the leptons have now been separately
discovered.
Each family now has two quarks and two leptons and this is displayed
in Fig. 10.1. There is no strict “monogamy” property among quarks in the
standard model, as shown by experiments. The quarks mix with each other.
Also we note that once the neutrinos are established to have mass (as we
see below), their monogamy property is spoiled. They will start mixing with
different charged leptons and will not remain monogamous as in the standard
model.