Quantum discovery verifies a decades-old theory on how monopoles decay

https://phys.org/news/2023-08-quantum-discovery-decades-old-theory-monopoles.html

"create Alice rings in nature... manipulated rubidium gas atoms prepared in nonmagnetic state near absolute zero temperature, creating a monopole by steering a zero point of a three-dimensional magnetic field into the quantum gas... Alice rings stable 84 ms, over 20X longer than monopole lifespan... ring a gateway to antimatter instead of matter... monopole passing through Alice ring's center transformed into opposite charged anti-monopole, and Alice ring's charge likewise changed"

Related: Diamonds and rust help unveil 'impossible' quasi-particles

https://phys.org/news/2023-12-diamonds-rust-unveil-impossible-quasi-particles.html