Diamagnetism
A universal weak magnetic property of matter where applied magnetic fields induce opposing atomic orbital currents that weakly repel the material.
Governing formula
χ_m < 0 (χ_m ~ -10⁻⁵)
SI unit
Dimensionless
In depth
Diamagnetism is a direct consequence of Lenz's law at the atomic scale. Superconductors act as perfect diamagnets (χ_m = -1), completely expelling internal magnetic fields (Meissner effect).
Examples in the real world
Pyrolytic graphite plates levitating stably above permanent magnet arrays, or bismuth exhibiting weak magnetic repulsion.