In a dramatic breakthrough that could change the way we use electricity, scientists have made a 60-watt light bulb glow by transmitting energy to it wirelessly. In the past, beaming electromagnetic energy has proven difficult because it scatters broadly, radiating in all directions rather than to just the intended electrical device. A series of successful experiments conducted at the Massachusetts Institute of Technology suggests otherwise, however. MIT physicists believe they can project a magnetic field from a length of wire whose ends nearly touch. The gap between the ends makes electrons surge back and forth at a specific rate, creating a magnetic field with a characteristic frequency. Since the electrons in a matching coil would have the same frequency, they would pick up the magnetic field. Just as a singer can break a crystal glass that resonates at the same frequency as her voice, the MIT scientists discovered how to get a recharging device and a power-hungry gadget to resonate at the same frequency, allowing the efficient exchange of energy. To prove their theory, the physicists — who dubbed the process WiTricity — used a pair of copper coils with a 2-foot diameter. One was […]