Research Article

On Relations between One-Dimensional Quantum and Two-Dimensional Classical Spin Systems

Table 1

The structure of functions and dictating the entries of matrices and , which reflect the respective symmetry groups. The s are the Fourier coefficients of the symbol of . Note that, for all symmetry classes other than , and thus .

Classical compact group Structure of matrices Matrix entries

  ,
if
if
either
or
,
,
,
,