Physicists have announced they are able to hide information in undetectable gaps in time.
The breakthrough relies on manipulating streams of light within optical fibres, rather than altering time itself.
Scientists are able to change how a beam of light travels on its path in the fibre, and use that principal to mask digital information which cannot be seen by an outside observer.
The study by researchers at Purdue University is published in the journal Nature.
They describe how the technique uses two phase modulators - the equipment in optical fibres which creates 'ones' and 'zeroes' out of light wave interference. One phase modulator creates the data, and the other covers it up.
Above: a basic diagram of the effect
The result is that the light looks like it's carrying no data, when in fact hardware at either end can decode the message.
Well... actually, that's the problem. Right now, it can't. The researchers explained that the current generation of the technology leaves the data totally irretrievable, even to the recipient at the other end. But they hope that with further research that will change, making the tech genuinely viable.
"It might be used to prevent communication between people, to corrupt their communication links without them knowing," said researcher Joseph Lukens.
"And you can turn it on and off, so if they suspected something strange was going on you could return it to normal communication."
Known as "temporal cloaking", the effect is not yet ready for practical use in security and telecoms.
But it is hoped that the principal may one day lead to more effective, stable and secure communications.
Built on 2012 research which cloaked very small amounts of time, the new research is able to hide relatively large amounts of information using off-the-shelf equipment.
The new technique is able to hide data 46% of the time - a "remarkable extension" according to Ortwin Hess, a physicist at Imperial College London.