DARPA gets that teensiest bit closer to making one:
Pentagon-supported physicists on Wednesday said they had devised a “time cloak” that briefly makes an event undetectable.
The laboratory device manipulates the flow of light in such a way that for the merest fraction of a second an event cannot be seen, according to a paper published in the science journal Nature.
It adds to experimental work in creating next-generation camouflage — a so-called invisibility cloak in which specific colours cannot be perceived by the human eye.
“Our results represent a significant step towards obtaining a complete spatio-temporal cloaking device,” says the study, headed by Moti Fridman of Cornell University in New York…
After proving that the “cloak” is possible, the next step for the researchers is to expand the time gap by orders of magnitude, firstly to microseconds and then to milliseconds, said Boyd and Shi.
The time cloak has a potential use in boosting security in fibre-optic communications because it breaks up optical signals, lets them travel at different speeds and then reassembles them, which makes data hard to intercept.
Last year, scientists reported a step forward in so-called metamaterials which act as a cloaking of space, as opposed to time.
Metamaterials are novel compounds whose surface that interacts with light at specific frequencies thanks to a tiny, nano-level structure. As a result, light flows around the object — rather like water that bends around a rock in a stream — as opposed to being absorbed by it.
Tinkering with time and space.