Quantum Cloud Simulates Magnetic Monopole
http://www.scientificamerican.com/article/quantum-cloud-simulates-magnetic-monopole/?WT.mc_id=SA_Facebook
Physicists have created and photographed an isolated north pole — a monopole — in a simulated magnetic field, bringing to life a thought experiment that first predicted the existence of actual magnetic monopoles more than 80 years ago.
In nature, north and south magnetic poles always go hand in hand. Cutting a bar magnet in half just creates two magnets, each of which still has two poles, rather than creating separate north and south poles on each half. Yet their electrostatic cousins, positive and negative charges, exist independently. In 1931, British physicist Paul Dirac theorized that if magnetic monopoles did exist, it would not only address this seeming imbalance, but would also explain why charge exists in discrete packages: multiples of the charge of a single electron.
more…