Impossible cube ambiguity present in a Necker cube illustration, in which a cube is drawn with its edges as line segments, and can be interpreted as being in either of two different three-dimensional orientations. An impossible cube is usually rendered as a Necker cube in which the line segments representing the edges have been replaced by what are apparently solid beams. In Escher's print, the top four joints of the cube, and the upper of the two crossings between its beams, match one of the two interpretations of the Necker cube, while the bottom four joints and the bottom crossing match the
The Cube Root of Uncertainty lush description and has a real love of calamity"). She noted that even the better stories were marked by "the sophomoric dark doom that most of us -- far less technically expert -- dealt with during our apprenticeships." The Cube Root of Uncertainty The Cube Root of Uncertainty is a collection of science fiction short stories by American writer Robert Silverberg, published in hardcover by Macmillan in 1970 and issued in paperback by Collier Books in 1971. No further editions have been issued. "Passengers" won the Nebula Award for Best Short Story and was nominated for the Hugo Award. Joanna