title: Magnetic catalysis versus magnetic inhibition.
abstract: We discuss the fate of chiral symmetry in an extremely strong magnetic field B. We investigate not only quark fluctuations but also neutral meson effects. The former enhances the chiral-symmetry breaking at finite B according to the magnetic catalysis, while the latter suppresses the chiral condensate once B exceeds the scale of the hadron structure. Using a chiral model, we demonstrate how neutral mesons are subject to the dimensional reduction and the low dimensionality favors the chiral-symmetric phase. We point out that this effect, the magnetic inhibition, can be a feasible explanation for recent lattice-QCD data indicating the decreasing behavior of the chiral-restoration temperature with increasing B.
authors: Department of Physics, Keio University, Kanagawa 223-8522, Japan.
authors: Kenji
authors: K
authors: Fukushima
authors: Yoshimasa
authors: Y
authors: Hidaka