Now you see it, now you don’t. Two words, invisibility cloaks. We all could use them once in a while. Researchers have begun to use carbon nanotubes together to make objects seem to vanish. The same principle that causes mirages, also can be used to create an “invisibility cloak” similar to that of Harry Potter’s.
The way it works is when heat changes the air’s temperature and density, light will bend, allowing strange things to appear or in this case, disappear. Unfortunately the only downside here is that right now you’ll need to do all your sneaking around, underwater.