Buildings may be 'cloaked' from earthquake

British mathematicians say a theoretical "cloaking" device that would be "invisible" to movement rather than light could protect buildings from earthquakes Researchers at the University of Manchester said by cloaking components of structures with pressurized rubber, powerful waves produced by an earthquake would not "see" the building and would simply pass around the structure and thus prevent serious damage or destruction. This "invisibility" could be vital safeguarding key structures such as nuclear power plants, electric pylons and government offices from destruction from natural or terrorist attacks, the researchers said in a university release Tuesday. While research into cloaking from light waves began some years ago, very little work has been done on waves such as those produced by earthquakes and their affect on solid bodies, they said. "Five or six years ago scientists started with light waves, and in the last few years we have started to consider other wave-types, most importantly perhaps sound and elastic waves," Manchester mathematician William Parnell said. "We showed theoretically that pre-stressing a naturally available material -- rubber -- leads to a cloaking effect from a specific type of elastic wave," he said. "Our team is now working hard on more general theories and to understand how this theory can be realized in practice."