The possibility of time travel has excited many of us for hundreds of years, inspiring countless books and films. The ability to move not only through space but into the past or future would open a myriad of possibilities for humankind.
But is it theoretically even possible to time travel?
In the original 1978 Superman film, Superman goes back in time by flying around the globe faster than the speed of light. This is incredibly fast – the speed of light is just under 300,000 km per second!
So far, we have not come even close to this speed, the fastest man-made object, a space probe, traveled at just 150 km per second.
Given the right technological advancements, is it theoretically possible for us to travel faster than the speed of light, and thus, like superman, travel in time?
We asked 6 experts in astrophysics, astronomy, and physics, ‘Is it possible to time travel by going faster than the speed of light?‘, here is what we found…
Do we experience time differently when we are traveling at speed?
Einstein’s theory of relativity determines that time is not universal – it is relative. The 1971 Hafele-Keating experiment found that a clock that was flown on an airplane traveling at speed fell behind clocks that remained on the ground.
More recently, precise atomic clocks have been found to run at different speeds when one is moved relative to the other. This phenomenon is called ‘time dilation‘.
Dr Sean Matt, an expert in astronomy and astrophysics from the University of Exeter in the UK, says, “If one travels close to the speed of light, time behaves differently than we are used to, and in this way, one can move forward in time faster than those left behind. So it is theoretically possible to travel to the future, but one could not return.”
Is it possible to travel faster than the speed of light?
All the experts agreed that it is not possible to travel faster than the speed of light, this is also specified in Einstein’s theory.
Dr Eric Tittley, an expert in astronomy and astrophysics from the University of Edinburgh, explains, “It is clear that no object or information can travel faster than the speed of light. It is not a question of not having enough energy to push it that fast. From an external perspective, any extra energy added to a body to get it to and past the speed of light just asymptotically accelerates it to the speed of light.”
‘Asymptotically’ meaning something gets closer and closer to the speed of light, but never quite reaches it.
No object can travel faster than the speed of light because as objects travel faster, they get heavier. Therefore, it is only light that can travel at the speed of light – because it has no mass.
The takeaway: Travelling at speed can change your experience of time, but time travel by traveling faster than the speed of light is sadly not possible.
Article based on 6 expert answers to this question: ‘Is it possible to time travel by going faster than the speed of light?’
This expert response was published in partnership with independent fact-checking platform Metafact.io. Subscribe to their weekly newsletter here.
