A minimal uncertainty in position measurement comes into play if, for instance, one incorporates gravitational interaction of photon and electron in the Heisenberg’s Electron Microscope Gedanken Experiment. This interaction modifies the Heisenberg’s standard uncertainty principle (HUP) to the so-called Generalized (Gravitational) Uncertainty Principle (GUP). The finite resolution of spacetime structure (through a minimal uncertainty in position measurement) nontrivially reflects the existence of a minimal measurable length of the order of the Planck length. The existence of such a minimal length is addressed in several approaches to quantum gravity proposal. On the other hand, Doubly Special Relativity (DSR) theories have revealed that due ...