'Invisibility cloak' could hide buildings from earthquakes

Posted by Kate Taylor

A team of British mathematicians has developed a theoretical design for a Harry Potter style ’cloaking’ device which could protect buildings from earthquakes.

Over the last year or so, scientists have come up with a number of cloaking devices working in different contexts. And Dr William Parnell of the University of Manchester says it's possible to use the same techniques to protect buildings and structures from vibrations and natural disasters such as earthquakes.

By cloaking components of structures with pressurised rubber, he says, powerful waves such as those produced by an earthquake would not ‘see’ the building – they would simply pass around the structure and thus prevent serious damage or destruction.  The building, or important components within it, could theoretically be ‘cloaked’.

This ‘invisibility’ could prove to be of great significance in safeguarding key structures such as nuclear power plants, electric pylons and government offices from destruction from natural or terrorist attacks, he says.

Scientists have been working on cloaking objects from light waves for about six years, but very little work has been done on waves in solid bodies, such as waves produced by earthquakes.

"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. The real problem with the latter is that it is normally impossible to use naturally available materials as cloaks," says Parnell.

"We showed theoretically that pre-stressing a naturally available material – rubber – leads to a cloaking effect from a specific type of elastic wave. Our team is now working hard on more general theories and to understand how this theory can be realised in practice."