Physics
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Introducing the 'antimagnet'
Researchers in Spain have proposed a new type of invisibility cloak that could hide objects from magnetic fields. The cloak – which has not been built yet – is designed to have a dual effect. It ensures that a magnetic field generated inside the cloak does not leak outside, and it ensures that the cloak and its contents cannot be detected by an external magnetic field. If it can be realized as a practical device, the technology could prove useful in industrial applications that require specific magnetic environments.
How to turn darkness into light
Quantum mechanics tells us that the vacuum is not empty but is filled with virtual particles that pop into and out of existence. Normally these particles are hidden from our view, but now a team of physicists has used the electrical equivalent of an ultrafast mirror to convert virtual photons into real electromagnetic radiation. Known as the dynamical Casimir effect, it was first predicted more than 40 years ago.