We suggest a mechanism that may resolve a conflict raised by Link between the precession of a neutron star and the standard picture in which its core is composed of a mixture of a neutron superfluid and a type-II proton superconductor. We will show that if there is a persistent, nondissipating current running along the magnetic flux tubes, the force between magnetic flux tubes may be attractive, resulting in a type-I, rather than a type-II, superconductor. If this is the case, the conflict between the observed precession and the canonical estimation of the Landau-Ginzburg parameter κ> 1 / √ 2 (which suggests type II behaviour) will be automatically resolved. Such a current arises in some condensed matter systems and may also appear in QCD dense matter as a consequence of quantum anomalies. We calculate the interaction between two vortices carrying a current j and demonstrate that when j> �c, where q is the charge of the Cooper pair and λ 2qλ is the Meissner penetration depth, a superconductor is always type-I, even when the cannonical Landau-Ginzburg parameter κ indicates type-II behaviour. If this condition is met, the magnetic field is expelled from the superconducting regions of the neutron star leading to the formation of the intermediate state where alternating domains of superconducting matter and normal matter coexist. We also discuss some instances where anomalous induced current may play a crucial role, such as the neutron star kicks, pulsar glitches and the toroidal magnetic field. PACS numbers: 97.60.Jd, 26.60.+c, 74.25.Qt, 97.60.Gb I
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