Science Fiction fans will be saddened to hear that we won’t be traveling through time, well at least not according to a group of Hong Kong scientists, who claim that their research proves it is impossible.
The team, which is based at the Hong Kong University of Science and Technology have said that it is just impossible for single photons to travel faster than the speed of light inside a vacuum. They will obey the laws of physics.
Professor Shengwang Du said in a statement “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. 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. Our findings will also likely have potential applications by giving scientists a better picture on the transmission of quantum information.”
This dismisses the discovery of “superluminal propagation of optical pulses” which claimed that a group of optical pulses could move faster than the speed of light. Du’s group of scientists measured the maximum speed of a single photon and it obeyed the speed limit laid out in the laws of physics. He said it “confirms Einstein’s causality; that is, an effect cannot occur before its cause.”
Publication SALON have a different take on the topic however and they claim that it may still be possible thanks to a phenomenon known as ‘time dilation’.
“Your velocity in space and time are inversely related, as dictated by Einstein’s theory of special relativity. Columbia physicist Brian Greene explains this weird feature of “space-time” in his seminal book, “The Elegant Universe”:
When an object moves [faster] through space relative to us, its clock runs slow compared to ours. That is, the speed of it’s motion through time slows down.”
They continue, saying “Time isn’t an absolute; it’s relative (hence “special relativity”). Your travel through time is malleable and manipulatable. And you can change how you experience it — albeit, ever so slightly — just by walking at a brisk pace.”
If you are starting to get lost, then they have published a theoretical example
“Let’s say you board a spaceship equipped with a rocket engine so powerful that you can travel at nearly the speed of light. And, let’s say you keep up this velocity, traveling away from Earth for what feels like six months; and then you turn around and head back toward Earth, which takes another six months. When you arrive back on our home planet, what you’ll find is that eons have passed. And who knows what you’ll find. Maybe everyone’s eating food in capsule form. Or maybe people are gone entirely, the whole of human history exhausted. While you’ve barely aged at all, the world as you knew it has changed quite a bit. Thus, time travel.”
Kitguru says: Time Travel is an unknown factor but we have always been interested in teleportation. Imagine being able to travel thousands of miles in an instant, without having to sit beside some sweaty overweight dude on a plane for 12 hours!