Trope-a-Day: Hard Light
Hard Light: Not strictly speaking.
What there is is the ontotechnological extrapolation of photonic molecules, quantum wells, programmable matter, and various other cutting-edge concepts until they resemble something like the reality graphics (and, indeed, the Eldraeverse calls them reality graphics) seen in Vernor Vinge’s A Fire Upon the Deep or the “false matter” seen in Greg Bear’s Anvil of Stars. In short: a way of creating projections that look and feel, so far as the universe is concerned, just like actual matter of whatever properties you feel like projecting.
(Although, unlike the shipbuilders of Anvil of Stars, Imperial engineers by and large prefer not to build starship hulls or other vital permanent structures from matter that disappears/decays when the projector is turned off…)