Exploratory engineering
Exploratory engineering is a term coined by K. Eric Drexler to describe the process of designing and analyzing detailed hypothetical models of systems that are not feasible with current technologies or methods, but do seem to be clearly within the bounds of what science considers to be possible within the narrowly defined scope of operation of the hypothetical system model. It usually results in paper or video prototypes, or (more likely nowadays) computer simulations that are as convincing as possible to those that know the relevant science, given the lack of experimental confirmation. By analogy with protoscience, it might be considered a form of protoengineering.