Abstract
Projecting a non-Abelian vacuum gauge field—a pure gauge constructed from the group element —onto a fixed (electromagnetic) direction in isospace gives rise to a nontrivial magnetic field, with nonvanishing magnetic helicity, which coincides with the winding number of U. Although the helicity is not conserved under Maxwell (vacuum) evolution, it retains one-half its initial value at infinite time.
- Received 15 November 1999
DOI:https://doi.org/10.1103/PhysRevD.61.105015
©2000 American Physical Society