22 Hints of Other New Physics from Neutrino Mass
167
Fig. 22.1 A possible way to search for mirror stars in the sky. Note that there are three
rays here from the source to the observer instead of two for a conventional planet or
star because light ray passes unhindered through the mirror star
22.2 Grand Unification of Forces and Matter
Searching for unified approach to forces and matter has been an eternal
goal of physicists. It may have started with Newton, who unified an apple
falling from the tree with the motion of planets around the Sun through
a common understanding of the laws of gravitation. Apparently unrelated
phenomena having the same explanation is after all the goal of unification.
Then came Maxwell’s unified approach to electricity and magnetism, which
are two manifestations of electric charge. When an electric charge is in motion,
it gives rise to magnetic forces. Einstein spent most of his life trying to unify
gravity with other forces. Kaluza and Klein provided one early example of such
unification using the five-dimensional extension of Einstein’s general theory of
relativity. The same dream of finding the ultimate unification of matter and
forces has lived on to the present day.
After the standard model of forces and matter was proposed, it was
suggested [80] that all matter and forces may be unified within certain large
symmetry groups called SU (5) and SO(10). In this approach, the observed
force strengths unify into one value at a very short distance of order of 10
−29
centimeters (see Fig. 22.2). The different force strengths we observe today are
a result of simply being at a larger distance, but there is only one force as we go
to really short distances. How small that distance is can be deduced by using
the rules of Quantum Field Theory. A larger symmetry group dictates how
matter and forces behave at these short distances. The choice of the symmetry
groups puts quarks and leptons into one group representation, which means
167
Fig. 22.1 A possible way to search for mirror stars in the sky. Note that there are three
rays here from the source to the observer instead of two for a conventional planet or
star because light ray passes unhindered through the mirror star
22.2 Grand Unification of Forces and Matter
Searching for unified approach to forces and matter has been an eternal
goal of physicists. It may have started with Newton, who unified an apple
falling from the tree with the motion of planets around the Sun through
a common understanding of the laws of gravitation. Apparently unrelated
phenomena having the same explanation is after all the goal of unification.
Then came Maxwell’s unified approach to electricity and magnetism, which
are two manifestations of electric charge. When an electric charge is in motion,
it gives rise to magnetic forces. Einstein spent most of his life trying to unify
gravity with other forces. Kaluza and Klein provided one early example of such
unification using the five-dimensional extension of Einstein’s general theory of
relativity. The same dream of finding the ultimate unification of matter and
forces has lived on to the present day.
After the standard model of forces and matter was proposed, it was
suggested [80] that all matter and forces may be unified within certain large
symmetry groups called SU (5) and SO(10). In this approach, the observed
force strengths unify into one value at a very short distance of order of 10
−29
centimeters (see Fig. 22.2). The different force strengths we observe today are
a result of simply being at a larger distance, but there is only one force as we go
to really short distances. How small that distance is can be deduced by using
the rules of Quantum Field Theory. A larger symmetry group dictates how
matter and forces behave at these short distances. The choice of the symmetry
groups puts quarks and leptons into one group representation, which means