Relative direction /

The most common relative directions are left, right, forward(s), backward(s), up, and down. No absolute direction corresponds to any of the relative directions. This is a consequence of the translational invariance of the laws of physics: nature, loosely speaking, behaves the same no matter what direction one moves. As demonstrated by the Michelson-Morley null result, there is no absolute inertial frame of reference. There are definite relationships between the relative directions, however. Left and right, forward and backward, and up and down are three pairs of complementary directions, each pair orthogonal to both of the others. Relative directions are also known as egocentric coordinates. Many human cultures use relative directions for reference. However, some do not. The Australian Aboriginal people the Guugu Yimithirr for instance, in their language have no words denoting the egocentric directions, but instead exclusively refer to cardinal directions, even when describing small-scale spaces. For instance, if they want someone to move over on the car seat to make room, they would say "move a bit to the east." To tell someone where exactly they left something in their house,