Wormhole solutions can arise from the third-rank field strength $H_{\mu \nu \rho }$ which has a gluon anomaly. The superstring axion has this property. The effect of these wormholes on axion cosmology is studied. To save the superstring axion energy-density problem, θ¯ is ∼${10}^{\mathrm{-}3}$ or ${\Lambda }_0^{1/4}$ is ∼10 keV at the QCD chiral-symmetry-breaking scale.

• Received 30 January 1989

DOI:https://doi.org/10.1103/PhysRevD.39.2444