The dream of invisibility has existed in popular culture from the H.G Wells novel published in 1897 to to Harry Potter and his invisibility cloak, and now, thanks to a whiz bang team of researchers at the University of Toronto, it is no longer the stuff of speculative fiction. The age of invisibility is upon us. Well, sort of.
The technology of the cloak was developed by two researchers in The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, Professor George Eleftheriades and PhD student Michael Selvanayagam, who have designed a type of cloak that differs from the previous invisibility technologies that have been experimented with in the past.
Invisibility cloak research became an area of study in 2006, when researchers attempted to cloak objects by covering them in layers and layers of metamaterials (synthetic materials that have properties not found in nature) in order to shield the objects from the electromagnetic radiation and light reflections that make objects perceivable to us. Though this tactic made sense scientifically, it was impractical for use on anything except very small objects, since the number of layers of material on top of the object that was trying to be concealed increased it's size so dramatically.
Eleftheriades and Selvanayagam's research differs from this idea of "layering", by simply surrounding an object in a cloak of small antennas that radiate an electromagnetic field. This radiated field cancels out waves that are reflected off an object normally, such as light, and without light reflected back to us, we are unable to detect that the object exists. Since these antennas are so much smaller and lighter, this version of an invisibility cloak is the first that is practical for real-world use on large and small objects alike, for uses from conducting surveillance or security operations, to sneaking off to the Chamber of Secrets after curfew.
To celebrate, here is a selection of "invisible" moments in popular culture.
The Invisible Man, 1933
Harry Potter tries out his invisibility cloak, 2001
The Invisible Woman, 1940