A correction to the Immirzi parameter of SU(2) spin networks

Abstract

The elegant predictions of loop quantum gravity are obscured by the free Immirzi parameter (. γ). Dreyer (2003), considering the asymptotic quasinormal modes spectrum of a black hole, proposed that γ may be fixed by letting the j=. 1 transitions of spin networks as the dominant processes contributing to the black hole area, as opposed to the expected j=. 1/2 transitions. This suggested that the gauge group of the theory might be SO(3) rather than SU(2). Corichi (2003), maintaining SU(2) as the underlying gauge group, and invoking the principle of local fermion-number conservation, reported the same value of γ for j=. 1 processes as obtained by Dreyer. In this note, preserving the SU(2) structure of the theory, and considering j=. 1 transitions as the dominant processes, we point out that the value of γ is in fact twice the value reported by these authors. We arrive at this result by assuming the asymptotic quasinormal modes themselves as dynamical systems obeying SU(2) symmetry.