They have named the machine a "Traversable Acausal Retrograde Domain in Space-time," the acronym for which is actually TARDIS.

Everyone knows that TARDIS really stands for "Time And Relative Dimensions In Space” but hell, even a Dr Who fanboy has to give the boffins an A for hammering a new meaning out of an old acronym.

The real-life machine imagined by physicists is, like the fictional TARDIS, shaped like a box that's capable of carrying passengers backwards and forwards through time and space. All that is needed to build it, say physicists, are the materials.

Ben Tippett of the University of British Columbia, mastermind behind the contrivance said that people think of time travel as something as fiction.

“We tend to think it's not possible because we don't actually do it. But, mathematically, it is possible.”

Tippett and colleague David Tsang from the University of Maryland have used Einstein's theory of general relativity to come up with their mathematical model for time travel.

They claim that the division of space into three dimensions, with time in a separate dimension by itself, is incorrect. Their model instead conceptualizes space-time as a continuum, whereby different directions are connected within the curved fabric of the universe.

Tippett said that time is curved in a comparable way to space: "The time direction of the space-time surface also shows curvature. There is evidence showing the closer to a black hole we get, time moves slower. My model of a time machine uses the curved space-time — to bend time into a circle for the passengers, not in a straight line. That circle takes us back in time."

The downside is that for the TARDIS to work, it would need to be built with some extremely exotic materials which have not been discovered yet. This is because a real TARDIS, which is mathematically possible, needs to withstand a jump through space-time.