Universe, group theoretical history

We have shown that the unitary group provides an organizing principle for much of matter - atoms, molecules, solids, nuclei and baryons. Note the particle number, N, is a unitary group-quantum number. Thus, the Greek concept of pure form, i.e. the group, is extended to include substance. The N = 0 space is a space without particle-number and hence without substance. The group theoretical history of our universe is shown in Fig. 12.1. 

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