Do UFOS use Dimension Doors

The ability to travel great distances has been noted in many encounters with UFOs. These strange craft seemed to vanish and then suddenly appear in another part of the heavens in almost the blink of an eye. I have long speculated that the use of some kind of dimensional travel was implicated. A surprising instance of this came to light while I was viewing one of the WebCams that I monitor for volcanic activity, Popocatepel is a Mexican volcano that is well known not only for its volcanic activity but additionally for the peculiar things often seen flying around it. The idea of dimensional travel is relatively easy, the only thing that separates distances is time. If you could dimensionally condense distance you would be able to travel across vast distances literally in the blink of an eye. It would more or less be like opening a door and stepping into somewhere else.