Where FTL is actually impossible is when something travels faster than the speed of light in a vacuum and the space it occupies is not folding or bending. If it were possible then this would be a true version of FTL and also a violation of physics as we know it. Why so? Well the short explanation is that it would violate laws of energy conservation and that is never a good thing to try; there is a lot of physics that has been measured to be correct and is underpinned by assumptions of energy conservation, so breaking that would cause many rules to be violated at once. Such rules are well founded with good reason and not something to overturn quickly. That’s why we can safely ignore any experiment that suggests to have created or detected particles (or signals) that travel faster than light.

You may recall the media frenzy when “scientists suggested that” certain neutrinos in the 2011 CERN experiment were travelling faster than light but it wasn’t so in the end. I was betting against this discovery being true.

The concept of folding space on the other hand is different. In such cases the rules of physics are bent but not violated. If the distance between two points decreases then the speed needed to travel between them can be smaller (for the same amount of time). Simple, nay? Fold space, stroll across to the other side. The bending, or folding, of space is not quite the same as wormholes which are a particularly special case of folded space. Wormholes could be created when two black holes connect with each other across a great distance; that is to say that it is more of a tunnel than just a simple fold. Picturing that is hard too as it is essentially a “bridge through a 4th dimension”.

Coming up next: an article on FTL in fiction. Comments / questions are always welcome.