viernes, junio 07, 2013

Scientists create device that tears a hole in time, enabling undetectable secret messages to be sent (so long as you do it in 0.00012 of a second)

A 'time cloak' which bends light to tear holes in time itself has been created by scientists.
The device could have important implications for sending secret messages via fibre optic cables.
The device can hide a continuous stream of events at telecommunications data rates - much quicker than a similar invention unveiled last year.

Researchers used equipment known as modulators to make the holes by bending light, reports Nature.
A 'time cloak' which bends light to tear holes in time itself has been created by scientists. The device can hide a continuous stream of events at telecommunications data rates
A 'time cloak' which bends light to tear holes in time itself has been created by scientists. The device can hide a continuous stream of events at telecommunications data rates
Although a long way off the fictional 'invisibility cloaks' featured in Star Trek and the Harry Potter films the concept could have practical applications to conceal messages.

A time or 'temporal' cloak that made a single event undetectable by speeding up and slowing down different parts of a light beam was described 17 months ago.
But this technique only hid single brief events over periods of 0.00012 of a second - too slow for optical communications.
Andrew Weiner and colleagues have now demonstrated an alternative method based on a phenomenon known as the Talbot effect when light passing through a grating travels in different directions.
The computer engineers found this could hide optical data from a receiver at telecommunications data rates.
Professor Andrew Weiner, of Purdue University in Indiana, said: ‘Through advances in metamaterials - artificially engineered media with exotic properties - the once fanciful invisibility cloak has now assumed a prominent place in scientific research.
‘By extending these concepts investigators have recently described a cloak which hides events in time by creating a temporal gap in a probe beam that is subsequently closed up - any interaction which takes place during this hole in time is not detected.

‘However these results are limited to isolated events that fill a tiny portion of the temporal period giving a fractional cloaking window which is much too low for applications such as optical communications.
Time cloaking is a way of manipulating electromagnetic radiation in time and space so a collection of events or happenings are concealed from people who are observing from a distance
Time cloaking is a way of manipulating electromagnetic radiation in time and space so a collection of events or happenings are concealed from people who are observing from a distance
‘Here we demonstrate another technique for temporal cloaking which operates at telecommunication data rates and by exploiting temporal self-imaging through the Talbot effect hides optical data from a receiver.
‘We succeed in cloaking 46 per cent of the entire time axis and conceal pseudorandom digital data at a rate of 12.7 gigabits per second.
‘This potential to cloak real-world messages introduces temporal cloaking into the sphere of practical application with immediate ramifications in secure communications.’
Despite the breakthrough it will likely be far in the future when scientists will have the ability to cloak time for an entire second or longer.
The device could have important implications for sending secret messages via fibre optic cables
The device could have important implications for sending secret messages via fibre optic cables
Time cloaking is a way of manipulating electromagnetic radiation in time and space so a collection of events or happenings are concealed from people who are observing from a distance.
In theory a thief could use time cloaking techniques to enter a building, steal cash or valuables and exit before their image was recorded on security cameras.
The concept employs the science of meta-materials in which light can be forced to behave in ways that it does not behave naturally.
Now research has proven it's possible, scientists are looking for ways to expand the amount of time that can be cloaked.
Time cloaking allows for data to be more secure because it separates optical signals - allowing them to travel at different speeds before being reassembled. This makes it more difficult for the data that is being transmitted to be intercepted.
A time lens may also allow information to be inserted into a continuous stream of data without disrupting the stream.
For example, a person who is streaming video on their iPad could potentially utilise time cloaking technology to create a gap that would allow them to download another file without interrupting their video.
But scientists estimate it would take a device about the size of our solar system for scientists to create a gap in time of eight minutes.
They are more concerned about terrorists using time cloaking technology to steal and record sensitive information without being detected.
Professor Weiner said: ‘Future cloaks based on our arrangement have the potential for significant improvements both in terms of operational bandwidth and the duration of the cloaked region.
‘Closely approaching the limit of 100 per cent would at present require too many modulators to be practical but it nonetheless remains a possibility for the future - nothing inherently prevents it.
‘From a more fundamental perspective our experiments highlight the efficacy of the Talbot effect for general cloaking.’

Read more: http://www.dailymail.co.uk/sciencetech/article-2336425/Scientists-create-device-tears-hole-time-enabling-undetectable-secret-messages-sent.html#ixzz2VXY0WIzi
Follow us: @MailOnline on Twitter | DailyMail on Facebook