If a "particle" (whatever that means) can travel faster than light, what would be the consequence? Simply put, you would see two things where only one exists. You would think particle A and B are separate but somehow linked by a mysterious force, when in fact what is happening is that you're looking at the same thing from two different perspectives at the same time.
Could be a little different. You can have a single particle that "looks" different, but symmetrical, from different points of view. If you have the observer travel faster than light, the observer will also think he is looking at several different things when he is in fact looking at the same thing from different, complementary perspectives. Does the word holographic come to mind? You bet.
By the way, the first and second paragraphs mean exactly the same thing.
Is superluminal travel possible? I don't know the answer, all I know is that superluminal travel is impossible to be measured by the very definition of light. But it's not a logical impossibility as far as I can see.
Think about it: what is the meaning of the imaginary result in the Lorentz transform when v > c? Sounds like elementary geometry to me: it means the object is no longer moving across t, it started moving along either x, y, or z. I don't understand why I never read about that before, sounds so elementary to me.