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The quest for a true invisibility cloak, seen in films such as Harry Potter, is the holy grail for physicists.

But while many have been able to briefly conceal objects from view, and even shield sounds, one team has developed a way to cloak entire events.

By concealing these events behind strands of laser light, the researchers could make it appear as if a moment - such as an object moving from one position to another - had spontaneously occurred of travelled inside a 'bubble of time.'

To create their 'temporal cloak', researchers separated strands of frequencies in light before changing their respective height. By slowing the speed of photons on a strand, the intensity of the light dropped to zero. This created a gap (illustrated in red), in which physicists could insert and send hidden data messages

The technique, called 'temporal cloaking' was developed at the Purdue University using lasers and fibre optics, and is reported in the journal Optics InfoBase.  

The researchers separated strands of light frequencies before changing their respective height.

They then sent this light through a fibre optic cable. 

By slowing the speed of photons on a particular strand, the intensity of that light dropped to zero.

This made that particular strand appear invisible, hidden behind or between other strands.

Using this method, the light travelling in front of this strand was sped up, while the trailing part was slowed down to create a gap.

The physicists then used this gap to insert hidden messages in data.

The hidden messages travelled along with the other frequencies, but arrived at the other end, marginally out of sync with the photons surrounding it.

The theory was proposed by scientists at Imperial College London in 2010, and the team of researchers from Purdue University made it a reality in 2013.

Last year, these experts concealed data, but were unable to retrieve this hidden data, and ultimately ended up erasing it.

They have since developed the technology, and their latest design is the first step towards using such cloaking devices in the real world.

Expanding this theory outside the realms of sending data, experts propose it has the potential to hide events featuring people, for example.

If a gap created between the light strands was large enough, a person could walk through the centre undetected, and appear in another location.

For example, if a pedestrian wanted to cross a road without interrupting the traffic, the cars that haven't reached the crossing would appear slowed down, while the cars beyond the crossing would speed up.

The theory (pictured) was proposed by scientists at Imperial College London in 2010, and a team of researchers from Purdue University made it a reality in 2013. Last year, these experts concealed data but were unable to retrieve it, and ultimately ended up erasing it. They have since advanced the technology

This would create a gap for the pedestrian to cross, but an observer looking from afar would only see a steady stream of traffic. This creates a 'bubble in time.'

To make such a large-scale cloak possible, it would require a system advanced enough to physically separate frequencies in light, which can then be manipulated - but the Purdue research proves it is at least possible.

And in theory, by changing the speed on multiple strands of light could create a series of gaps into which multiple pieces of data could be hidden.

Lead researcher Joseph Lukens said: 'It looks like no signal is being sent and [adds] a potentially higher level of security because it doesn't even look like you are communicating.

'Eavesdroppers won't realise the signal is cloaked because it looks like no signal is being sent.' 

Expanding this theory, experts propose it could potentially be used to hide people, for example. If a gap created between the strands was large enough, a person could walk through undetected, and appear in another location. This would making them appear to have been transported, like in Star Trek (pictured)

The technology is called a spacetime cloak because the data is transported in a 'bubble of time.' Other researchers have created cloaks that conceal objects (similar to that seen in Harry Potter pictured) by curving light, as well as shield sounds from certain people