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The idea of '''space''' has been of interest for [[philosophy|philosophers]] and [[science|scientists]] for much of human history. The term is used somewhat differently in different fields of study, hence it is difficult to provide an uncontroversial and clear definition outside of specific defined contexts. Disagreement also exists on whether space itself can be measured or is part of the measuring system. (See [[#In philosophy|Space in philosophy]].)   

The idea of '''space''' has been of interest for [[philosophy|philosophers]] and [[science|scientists]] for much of human history. The term is used somewhat differently in different fields of study, hence it is difficult to provide an uncontroversial and clear definition outside of specific defined contexts. Disagreement also exists on whether space itself can be measured or is part of the measuring system. (See [[#In philosophy|Space in philosophy]].)   

Science considers space to be a fundamental quantity (a quantity which can not be defined via other quantities because other quantities - like [[force]] and [[energy]] - are already defined via space).  Thus an [[operational definition]] is used in which the procedure of [[measurement]] and the units of measurement are defined. All properties of space then follow from this definition.

Science considers space to be a fundamental quantity (a quantity which can not be defined via other quantities because other quantities - like [[force]] and [[energy]] - are already defined via space).  Thus an [[operational definition]] is used in which the procedure of [[measurement]] and the units of measurement are defined. All properties of space then follow from this definition.

==In philosophy==

==In philosophy==

Space has a range of definitions:

Space has a range of definitions:

*One view of space is that it is part of the fundamental structure of the universe, a set of [[dimension]]s in which [[object (philosophy)|object]]s are separated and located, have size and shape, and through which they can move.

*One view of space is that it is part of the fundamental structure of the universe, a set of [[dimension]]s in which [[object (philosophy)|object]]s are separated and located, have size and shape, and through which they can move.

*A contrasting view is that space is part of a fundamental [[Abstract structure|abstract]] mathematical [[concept]]ual framework (together with [[time]] and [[number]]) within which we compare and [[quantity|quantify]] the distance between objects, their sizes, their shapes, and their speeds. In this view, ''space'' does not refer to any kind of entity that is a "container" that objects "move through".

*A contrasting view is that space is part of a fundamental abstract mathematical [[concepts|concept]]ual framework (together with [[time]] and [[number]]) within which we compare and [[quantity|quantify]] the distance between objects, their sizes, their shapes, and their speeds. In this view, ''space'' does not refer to any kind of entity that is a "container" that objects "move through".

These opposing views are relevant also to definitions of time. Space is typically described as having three dimensions, see [[Three-dimensional space]] and that three numbers are needed to specify the size of any object and/or its location with respect to another location. Modern [[physics]] does not treat space and time as independent dimensions, but treats both as features of [[space-time]] &ndash; a conception that challenges intuitive notions of distance and time.

These opposing views are relevant also to definitions of time. Space is typically described as having three dimensions, see [[Three-dimensional space]] and that three numbers are needed to specify the size of any object and/or its location with respect to another location. Modern [[physics]] does not treat space and time as independent dimensions, but treats both as features of [[space-time]] &ndash; a conception that challenges intuitive notions of distance and time.

As far as the concept of [[Dimension#Mathematical dimensions|dimension]] is defined, although [[three-dimensional space]] is the most commonly thought of dimensional space, the number of dimensions for a space to exist need not be three: it can also be zero (a point), one (a line), two (a plane), more than three, finite or infinite, and with some definitions, a non-integer value. Mathematicians often study general structures that hold regardless of the number of dimensions.

As far as the concept of [[Dimension#Mathematical dimensions|dimension]] is defined, although [[three-dimensional space]] is the most commonly thought of dimensional space, the number of dimensions for a space to exist need not be three: it can also be zero (a point), one (a line), two (a plane), more than three, finite or infinite, and with some definitions, a non-integer value. Mathematicians often study general structures that hold regardless of the number of dimensions.

===In physics===   

===In physics===   

==References==

==References==

* [http://search.eb.com/eb/article?tocId=46639 Space perception]. ''Encyclopædia Britannica'' from Encyclopædia Britannica Online. Accessed June 12, 2005.

* [https://search.eb.com/eb/article?tocId=46639 Space perception]. ''Encyclopædia Britannica'' from Encyclopædia Britannica Online. Accessed June 12, 2005.

[[Category: General Reference]]

[[Category: General Reference]]