# Mathematician Calculates Possibility of Time Travel

In a news release published April 27th, University of British Columbia - Okanagan mathematics and physics instructor Ben Tippett announced publication of a study that predicts the possibility of time travel. Tippett, whose field of expertise is Einstein's theory of general relativity, says that he used math and physics to generate a formula that describes a method for time travel.

“People think of time travel as something fictional,” says Tippett. “And we tend to think it’s not possible because we don’t actually do it. But, mathematically, it is possible.”

Tippett claims that the division of space into three dimensions, with time in a separate dimension by itself, is incorrect. Instead, the four dimensions should be imagined simultaneously, with different directions connected as a space-time continuum. In the study, Tippett explains that the curvature of space-time accounts for the curved orbits of the planets.

In uncurved space-time, planets and stars would move in straight lines. But in the vicinity of a massive star, space-time geometry becomes curved, and the straight trajectories of nearby planets follow the curvature and bend around the star.

“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,” says Tippett. “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.”

Although it is possible to describe mathematically a machine capable of performing such an act, Tippett doubts that it will ever be built.

“H.G. Wells popularized the term ‘time machine’ and he left people with the thought that an explorer would need a ‘machine or special box’ to actually accomplish time travel,” says Tippett. “While is it mathematically feasible, it is not yet possible to build a space-time machine because we need materials—which we call exotic matter—to bend space-time in these impossible ways, but they have yet to be discovered.”

Fans of the popular science fiction show Doctor Who will recognize the acronym chosen for the mathematical model that Tippett used for his research. Known as the Traversable Acausal Retrograde Domain in Space (TARDIS), he describes it as a bubble of space-time geometry which allows those within it to travel backwards and forwards through time and space, as interpreted by an external observer, as it tours a large circular path. The bubble moves through space-time at speeds greater than the speed of light at times, allowing it to move backward in time.

“Studying space-time is both fascinating and problematic. And it’s also a fun way to use math and physics,” says Tippett. “Experts in my field have been exploring the possibility of mathematical time machines since 1949. And my research presents a new method for doing it.”

Tippett’s research was recently published in the IOPscience *Journal Classical and Quantum Gravity. *