Magnetic winding: what is it and what is it good for?
Christopher Prior, David MacTaggart
2020Proceedings of the Royal Society A Mathematical Physical and Engineering Sciences21 citationsDOIOpen Access PDF
Abstract
Magnetic winding is a fundamental topological quantity that underpins magnetic helicity and measures the entanglement of magnetic field lines. Like magnetic helicity, magnetic winding is also an invariant of ideal magnetohydrodynamics. In this article, we give a detailed description of what magnetic winding describes, how to calculate it and how to interpret it in relation to helicity. We show how magnetic winding provides a clear topological description of magnetic fields (open or closed) and we give examples to show how magnetic winding and helicity can behave differently, thus revealing different and important information about the underlying magnetic field.
Topics & Concepts
PhysicsMagnetic fieldHelicityMagnetic helicityMagnetic energyInvariant (physics)Magnetic domainCondensed matter physicsIdeal (ethics)Demagnetizing fieldTheoretical physicsMagnetMagnetic fluxTopology (electrical circuits)Winding numberQuantum entanglementMagnetic dipoleMagnetic reactanceElectromagnetClassical mechanicsSolar and Space Plasma DynamicsFluid dynamics and aerodynamics studiesQuantum and Classical Electrodynamics