This means the Kickstarter’s appeal of life-size free-floating holograms without screens is an internal contradiction. In order to have a life-size hologram, you need to have a life-size screen behind it. Why? Because light travels in straight lines (more or less, at least). What I mean to say is that this is not just “ambitious,” or “far thinking,” or “technically hard;” this is impossible, at least until we invent a completely new set of natural laws. See Figure 4 for a simple diagram.