Dreibein

Three orthonormal vectors #92;hat#123;l#125;, #92;hat#123;e#125;#123;(1)#125; and #92;hat#123;e#125;#123;(2)#125; form the dreiben - a local physical coordinate frame of the A-phase vacuum.

This is shown for the following canonical sectors: i) a conformally invariant generic description where the spinor field and the dreibein are locally rescaled; ii) a specific configuration for the Dirac fermion consistent with its spin, where Weyl symmetry is exchanged by time reparametrizations; iii) the vacuum sector 1, which is of interest for perturbation theory.