Invisibility cloaks have already been demstrated for radar, sonar and acoustic waves, but now researchers think that they can render buildings invisible to earthquakes! If this technology is proven out experimentally, then metamaterials could become standard equipment in the foundations of every new building constructed worldwide. R.C.J.
Earthquakes can be made to bypass buildings surrounded by seismic invisibility cloaks, claim researchers at the University of Liverpool. Just as submarines can be shielded from sonar, airplanes from radar and small areas from probing by laser beams, the very long wavelengths emanating from earthquakes can likewise be redirected around buildings, effectively making them "invisible" to seismic waves. Invisibility cloaks work by harnessing metamaterials--regular patterns of dielectrics that resonate at the cloaking frequency. The technique effectively diverts electromagnetic energy around objects. Experimental confirmation of the metamaterials is underway, and the researchers also are experimenting with methods for diverting shock waves around passengers during automobile accidents.