Invisibility cloaks and stealth technologies depend on deflecting light or sound waves around an object, making it unseen or unheard.
Some of the newest cloaking techniques depend on using exotic manmade metamaterials. But a team of researchers led by William Parnell at the University of Manchester has found that ordinary rubber can make buildings invisible — at least to earthquakes.
The idea is pretty simple: Build a giant rubber bumper, fill it with air or some other pressurized fluid,, and install it around the foundation of a building or other structure. When an earthquake strikes, the bumper deflects the seismic waves away from the structure, like water flowing around a rock in a stream.
This would work, at least in theory, because of how seismic waves travel through the ground. They move through dense rock and soil unimpeded, but when they encounter a pressurized, air-filled substance, they change direction, just as light waves do when they pass through a prism or water. The bumper would essentially bend the waves around the building.
The idea would also work against explosives, so it isn't just for earthquakes — it also might be a way to protect buildings from terrorist attacks, at least if they are aimed at bringing down the structure.
It wouldn't be practical to retrofit every building with this kind of thing. But power lines, government buildings or other important structures could have such bumpers installed.
Top photo: An apartment building in Chile rattled by the magnitude 8.8 earthquake on Feb. 27, 2010. Credit: Wikimedia / Jorge Barrios