Journal of High Energy Physics (Apr 2020)

Magnetogenesis from a rotating scalar: à la scalar chiral magnetic effect

  • Kohei Kamada,
  • Chang Sub Shin

DOI
https://doi.org/10.1007/jhep04(2020)185
Journal volume & issue
Vol. 2020, no. 4
pp. 1 – 30

Abstract

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Abstract The chiral magnetic effect (CME) is a phenomenon in which an electric current is induced parallel to an external magnetic field in the presence of chiral asymmetry in a fermionic system. In this paper, we show that the electric current induced by the dynamics of a pseudo-scalar field which anomalously couples to electromagnetic fields can be interpreted as closely analogous to the CME. In particular, the velocity of the pseudo-scalar field, which is the phase of a complex scalar, indicates that the system carries a global U(1) number asymmetry as the source of the induced current. We demonstrate that an initial kick to the phase-field velocity and an anomalous coupling between the phase-field and gauge fields are naturally provided, in a set-up such as the Affleck-Dine mechanism. The resulting asymmetry carried by the Affleck-Dine field can give rise to instability in the (electro)magnetic field. Cosmological consequences of this mechanism are also investigated.

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