frame of reference A mathematical coordinate system for describing events in space and time with respect to a given observer. In relativity theory, this frame of reference is four-dimensional and the description of events in other frames of reference depends on the relative velocities and accelerations of those frames with respect to the frame of reference of the observer. Related category • SPACE AND TIME Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) |