Theoretical Physicists have conceived of an invisibility cloak that not only makes an object invisible, it erases any trace of its history during the time it is invisible.
“Light normally slows down as it enters a material, but it is theoretically possible to manipulate the light rays so that some parts speed up and others slow down,” said McCall.
When light is ‘opened up’ in this way, rather than being curved in space, the leading half of the light speeds up and arrives before an event, whilst the trailing half is made to lag behind and arrives too late. The result is that for a brief period the event is not illuminated, and escapes detection. Once the concealed passage has been used, the cloak can then be ‘closed’ seamlessly.
Such a space-time cloak would open up a temporary corridor through which energy, information and matter could be manipulated or transported undetected. “If you had someone moving along the corridor, it would appear to a distant observer as if they had relocated instantaneously, creating the illusion of a Star-Trek transporter, McCall said. “So, theoretically, this person might be able to do something and you wouldn’t notice!”
Of course, this is all a theory for now. But such an invention would allow for some amazing applications. Untraceable communications, for one.