Several years ago, Stephen Hawking wrote an article where he thought that limited time travel was a remote possibility, if one would only go into the future, through a wormhole using a massive particle collider and a super fast spacecraft. In sum, unrealistic and impossible to pull off.
Some scientists began to believe time travel might actually be possible when superluminal -- or faster-than-light -- propagation of some specific medium were discovered. It was later found to be a visual effect, but the idea that a single photon could exceed the speed of light lingered, and with it, the possibility of time travel.
But in a study published in the peer-reviewed scientific journal Physical Review Letters, Shengwang Du and his team measured the ultimate speed of a single photon and showed that it cannot move faster than the speed of light.
"The results add to our understanding of how a single photon moves. They also confirm the upper bound on how fast information travels with light," Du said in a statement put out by the Hong Kong University of Technology and Science.
"By showing that single photons cannot travel faster than the speed of light, our results bring a closure to the debate on the true speed of information carried by a single photon."
So Time Travel is impossible. The scientific basis for the science fiction application of the literary format of the genre is for naught. The light, from the Cave or the Frozen Donkey Wheel, could not have created the LOST characters from time traveling in our physical world.
