A problem with your arguments regarding the energy requirements, that only applies when your teleportation is momentum based, see: Dragon Ball Instant Transmission<br>Some forms of teleportation are simply "Think of a point in space, and you go there" they aren't running or moving, they're just disappearing, and appearing elsewhere so, teleportation isn't momentum based, it's just like, a wormhole, displacing oneself... that sound effect for your vanishing? that could easily be a vacuum sound as air fills the space you once were, however, where you appear would have a pop as you displace the air where you previously were, unless of course if your teleportation is between fixed spaces, in which case, the air in the teleportation chamber swaps places with the air in the other teleportation chamber...