The secret of invisibility
2006/07/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria
How can an object be converted into invisible? It is easy: from where you look, instead of the object, showing the light that comes from behind the object. In the city a car will be invisible if looking at the car you see the other side of the car, like the sidewalk in front. Yes, but how can it be done?
Theoretical physicists have the answer. The truth is that there are many ways and the last one has been proposed at the prestigious Imperial Colledge in London. The idea is to bend the rays of light; if the light coming from the car on the opposite sidewalk, instead of hitting the car, surrounds it and continues in the opposite direction, the viewer will see what is behind the car, the sidewalk and not the car itself.
To do this, light rays must be channeled to your liking. According to London physicists, this could be done through metamaterials, materials with a negative refractive index. This means they can divert light in any direction. Therefore, the integration of this material on the outside of the object allows its invisibility.
It is a theoretical idea, but these metamaterials exist today, they have already been made by engineers in the laboratory. For physicists, the same could be done with other waves, such as radio waves, to protect any object from those waves. It is a theoretical idea, but can soon be carried out in the laboratory.
