1. CMB 1999 (vol 42 pp. 248)
|The Classification of $\Pin_4$-Bundles over a $4$-Complex |
In this paper we show that the Lie-group $\Pin_4$ is isomorphic to the semidirect product $(\SU_2\times \SU_2)\timesv \Z/2$ where $\Z/2$ operates by flipping the factors. Using this structure theorem we prove a classification theorem for $\Pin_4$-bundles over a finite $4$-complex $X$.
Categories:55N25, 55R10, 57S15