Physicists solve 40-year-old magnetic mystery

Physicists solve 40-year-old magnetic mystery Sarah Collins Tue, 08/25/2026 - 11:05 A quantum particle that crosses a ‘duality defect’ – a boundary between order and disorder – is never reflected. It always passes through, but it comes out changed: not a particle, but a spread-out, thread-like excitation that researchers compare to a wisp of fog. The findings, published in the journal Nature Physics , may help solve a 40-year-old puzzle in physics known as the magnetic monopole paradox.