# Does antimatter travel faster than light?

I have read in the answers here that an electron traveling backwards in time would behave as a positron. I also read in another there that antimatter is matter traveling backwards in time

As far as I know as something travels faster time slows down according to the laws of relativity. For something traveling at the speed of light time stops.

So if antimatter is matter traveling backwards in time wouldn't that mean antimatter is traveling faster than light?

• Nothing is traveling backwards in time and there is no difference between matter and antimatter in this respect. This particular meme is about as false as things can get in physics. It is derived from a symmetry property of Feynman diagrams, but those are little pictures that make life easier for physicists who have to calculate perturbation series in particle physics, they are not actual physical reality. What it really means is that the modified process to the one in a diagram is also possible if we replace particles in the diagram with their anti-particles and reverse the directions. Mar 22, 2016 at 4:32
• There is only one arrow of time-forward.....antimatter or otherwise, nothing can travel 'backward' in time. Mar 22, 2016 at 4:40
• In addition to the above, traveling backwards in time isn't the same as traveling faster than light. Particles that travel "backwards in time", which is more of a statement based on models than a statement of fact, still have to obey the laws of relativity and can't travel faster than light. Imagine filming a car driving down the road, now, run the film backwards. In neither viewing is the car traveling faster than light, it's simply reversed direction. Mar 22, 2016 at 4:49
• Good point @userLTK but I believe the OP is talking about the relativistic transformations which mathematically (makes no physical sense) allow for time to stop at speed of light, and move backward if you exceed it. Keyword being, 'mathematically'. Mar 22, 2016 at 5:02
• @GRrocks: There is no such transformation in special relativity, folks are just not looking carefully enough at signs and resulting imaginary constants from square roots when they claim that there is. Mar 22, 2016 at 5:11