Ok, I'll try & lay the picture as best as possible. I'm on a spaceship & have a laser on the floor pointing towards the ceiling. When I'm not accelerating the laser shoots up & hits the ceiling. No problem there. If I'm accelerating at a fast enough pace the laser wouldn't go straight to the ceiling. We'll say it shoots out & hits the wall to my left while the ship is accelerating straight ahead. If the wall to my left was a mirror, where would the light then reflect to? Here is a basic picture http://img155.imageshack.us/img155/740/spaceship3hp.jpg [Broken] (red box = laser, blue line = light beam). I don't understand the math behind all this just yet but I'm just trying to get a basic understand for which direction the light would travel. Would it bounce straight back in the same direction? Head towards the ceiling? Curve again & hit the wall? or something totally different?