Space
In physics, space is defined as a coordinate system where you can locate an object. In classical physics the space is a three-dimensional Euclidean space where any position can be described using three coordinates. In relativistic physics, one talks about spacetime rather than about space; spacetime is modeled as a four-dimensional manifold.
See also: Spherical coordinates, Cartesian coordinates
Space is the relatively empty parts of the Universe, outside the atmospheres of planets. It is sometimes written as outer space to distinguish it from airspace and terrestial locations.
See also: space science; Astronomy and Astrophysics
The term inner space has sometimes been used to describe the contents of the human mind.
See also: psychology
Philosophical questions concerning space include: Is space absolute or purely relational? Does space have one correct geometry, or is the geometry of space just a convention? Historical Eminences who have taken sides in these debates include Newton (space is absolute), Leibniz (space is relational), and Poincaré (spatial geometry is a convention).
Here are two important thought-experiments connected with these questions: Newton's bucket argument and Poincaré's disc-world.
See also Philosophy of Physics
In mathematics, a space is a set, usually with some additional structure. For examples, see Euclidean space, vector space, normed vector space, Banach space, inner product space, Hilbert space, topological space and metric space.