Physicists Claim To Be Able To Realize The Dream Of A Time Machine

Physicists have thought of what they say is a mathematical model of a theoretical "time machine" - something like a box which can move backward and forwards through space and time.

As they state, the trick is to use the curvature of time and space in the Universe in order to bend time into a circle for the hypothetical passengers sitting in the box. That circle will let them travel in the future and the past.

Ben Tippett, theoretical physicist and mathematician from the University of British Columbia in Canada, and David Tsang, an astrophysicist at the University of Maryland, have used Einstein's theory of general relativity to discover a mathematical model of what they've named a Traversable Acausal Retrograde Domain in Space-time.

However, before we become crazy with the idea of time traveling, we should know, as the researchers note, that this won't be created tomorrow.

According to Tippett and Tsang, the materials required for a time machine to be built are... exotic and still undiscovered.

But what's their main idea?

The model is based on the thought that instead of seeing the Universe in 3 spatial dimensions, with the 4th dimension (time) separated, we could imagine those 4 dimensions simultaneously.

That would let us consider the chance of a space and time continuum, where all different directions in space and time are connected in the curved fabric of the Universe.

Einstein's theory of relativity connects gravitational effects in the Universe to a curvature of space and time.

If space and time were uncurved, planets would move in straight lines. However, according to the theory of relativity, the geometry of space and time becomes curved in the vicinity of high-mass objects, which instead makes planets to bend their paths and rotate around their star.

What Tippett and Tsang discuss is that it's not only physical space that can be bent and twisted within the Universe; time itself can also twist in the vicinity of high-mass objects.

To harness this theoretical property, the physicists suggest creating a type of 'bubble' of space-time geometry, that carries whatever is inside it through space-time along with a large circular path.

In case this bubble can hit speeds greater than the speed of light - which, according to the physicists is mathematically possible - that would let it move backward in time.

You can see the main idea in the picture below, with a passenger into the bubble/time machine (that's person A), and an external observer who is standing beside it (that's person B).

The arrow of time - which in our Universe always points forward, making the present coming after the past - is shown by the black arrows:


B. K. Tippett et. al.
Both person A and person B are experiencing time in totally different ways.

Unfortunately, Tippett and Tsang's idea still lacks the right materials needed for a time machine to be built.

Their idea recalls a former theoretical time machine - the Alcubierre drive, that would also use a shell transport passengers through time-space.

Both ideas can't be realized without some thinking on how to actually produce these materials. However, as Tippett points out, people are never going to stop exploring the possibilities of time travel, since it's a field "both fascinating and problematic,".

The research has been published in Classical and Quantum Gravity.

Reference: Science Alert

Written by Katerina Papakyriakopoulou

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